Mobile Communications

Digital Rights Management (DRM)

2007-07-04T01:05:00.000-07:00

The use of mobile and portable devices to download and use content raises the
issues of rights management. The originator of the content, whether music, images,
movies or games, will have spent a lot of time and money developing that content
and will want to exert some control over the future use of that content. This is
where DRM systems can be applied to limit the use, and therefore prevent misuse
of content.

There are a large number of proprietary DRM systems at present, which reflects
the growing availability of digital content over the Internet and other networks,
and is indicative of the lack of standards in this area. The Open Mobile Alliance
(OMA) has worked on enablers for DRM systems aimed at mobile handsets and
other portable devices, and many handset manufacturers now support OMA DRM
but may also support proprietary techniques as the market dictates. DRM systems
are built around a trusted entity known as a DRM agent (or client), which in the
case of a mobile network resides in the handset.

The DRM client is able to download content and the rights to use that content.
The content and rights can be kept separate or can be delivered in a combined format.
Rights are a mixture of permissions and constraints that indicate what can
be done with the associated content.

For example, content may be valid for 30 days, or until the end of the month;
the number of plays may be limited; etc. It is the responsibility of the DRM agent
to apply the rights to the content and to track its usage, so that if, for example, it
is a song that can only be played 30 times, then the content cannot be used unless
new rights are obtained.

OMA release 1 DRM included a number of basic features, which were forward
lock (preventing content forwarding), combined delivery, and separate delivery.
Separate delivery, where the content and rights are kept separate, supports something
known as super-distribution, whereby users are able to distribute content at
will, but not the rights for that content. This can be very useful where the content
has some sort of preview mode that can be used to encourage recipients to acquire
their own rights to that content.

Press-to-Talk

2007-07-04T01:04:00.000-07:00

Press-to-Talk (PTT) service is a real-time, point-to-point and point-to-multipoint,
voice-based instant messaging application. This has proved a popular service in the
United States on the Nextel network, based on Motorola’s iDEN architecture. Many
of the features are the same as text-based IM, with buddy lists and chat rooms, etc.
Once again, the biggest potential problem affecting the widespread adoption of the
service will be compatibility between handsets and across networks.

There are, at present, four PTT solutions on the market.

1. Motorola iDEN. This is a well-established system that has a proven track
record in the United States with good performance. Motorola also supplies
a wide range of handsets to support the service. However, only Motorola
manufactures handsets for this service. iDEN does not support a presence
service.

2. Kodiak. This system uses circuit-switched connections, which results in good
performance but misses out on the efficiency of packet-based delivery. The
system is also technology-agnostic. It has been deployed on GSM, CDMA,
and analog networks. However, there is a limited range of handsets available
for this service. Kodiak has a thin-client available to allow vendors to implement
the service.

3. Qualcom Qchat. This service is proprietary to Qualcom and is only supported
on cdmaOne 1X only. In this case, the performance of the 1X network may
not be sufficient to ensure adequate performance. The QChat service is implemented
on Qualcomm’s BREW platform.

4. PTT over Cellular (PoC). The final method is a proposed standard mechanism
from Ericsson, Nokia, Motorola, and Siemens for a PTT over Cellular
(PoC) system. This has been presented to the Open Mobile Alliance (OMA),
which is developing this proposal as a standard in line with the 3G UMTS
and IMS specification from the 3GPP. It is based, generally, on existing protocols
and methods: IP and SIP. This system has the advantage that it will
run over any network. There will be products available in GSM and GPRS,
UMTS, and cdma2000. It is anticipated that it will be possible to interoperate
a PTT service across network boundaries.

DVB-H and UMTS

2007-07-04T01:03:00.000-07:00

Studies have been conducted in relation to the roll-out of DVB-H and its possible integration
with cellular networks. DVB-H is backward-compatible with DVB-T, and
the two formats can be mixed in the same digital multiplex. While one multiplex can
convey six to eight DVB-T channels, it can be used for up to fifty DVB-H channels.
The DVB technology can be kept separate and used to deliver content to DVBH-
enabled terminals, or a cellular technology, such as UMTS, could be used to
provide a reverse channel that allows users to browse for content and, when content
selection is made, have that content delivered over a DVB-T channel (Figure 4.67).
This would mean that some degree of cooperation would be required between the
UMTS network operator and a broadcaster. The convergence of telecommunications
and entertainment services means that such cooperation is very likely.

Services and Security for Handset

2007-07-04T01:02:00.000-07:00

Given the range of mobile device capability in today’s market, there are many types
of service that may be available to the user. Some of these services depend on handset
capability; others rely on the services supported by the network.
Until recently, many services relied on proprietary techniques in the handset
or network, which means that services are often limited to just a certain handset
model or are only available with a particular mobile operator. The process of defining
services by organizations such as 3GPP has led to the standardization of many
services, or the development of standard environments where services can be developed,
deployed, and executed.

Described below are some of the services that can be seen on handsets that
are available today. All of these services have benefited from the process of
standardization.

Support for Location Technologies
There are a number of techniques for providing location information for handsets.
Some of these require involvement of the handset in the location process; others use
data that is already collected by the handset during normal modes and operation
and do not place additional processing requirements on the handset.
The least accurate location technique uses either Timing Advance (TA) in GSM
or Cell Identity (Cell ID) in UMTS. When a mobile connects to the network (in
dedicated mode), the TA or Cell ID is known and can be reported to a location
server and used to deliver some form of location service to the user. More accurate
location information can be obtained using a triangulation process, wherein the
handset measures information from multiple base stations and uses this, along with
data obtained from the network, to calculate the true time differences of the signals
it has received.

In GSM, this technique is known as Observed Time Difference of Arrival
(OTDOA). In UMTS, the equivalent process is Enhanced-Observed
Time Difference (E-OTD). In both cases, the handset measures the time difference
of signals between base stations; it also receives information about the real-time difference
(either sent by broadcast messages or to one specific mobile) and it calculates
from these a geometric time difference. This geometric time difference is the result
of location and can be reported to the network to deliver location services. This
calculation requires some additional processing in the handset.

The final location mechanism is potentially the most accurate, and involves integrating
a GPS receiver in the handset. When required, the handset
can take GPS measurements and report these to the location servers in the network.
To speed the satellite acquisition process, the network can broadcast assistance
data, which tells handsets in a particular area which satellites are visible. GPS-based
location has the largest impact on the mobile because of the GPS receiver and the
processing that is required to resolve position information. It is possible to combine
location techniques; thus, for example, when GPS fails to give a fix because the
handset is inside a building, the location information could be obtained from the
time-difference techniques.

Mobile TV Reception
The multimedia capabilities of handsets have raised the possibility of delivering
television to mobile or handheld devices, and indeed a number of services have
been launched that allow users to download short video clips and even video ringtones
onto their phones.

However, these services are using the bearers or channels in the 2.5G or 3G
network, which in many cases may not have the bandwidth or the format to support
high-quality video transmission. There is also an impact on all other services.
Because video has a relatively high bandwidth, it will limit the capacity for all the
other services delivered by the network.

A possible solution is the use of a technology known as Digital Video Broadcast-
Handheld (DVB-H). DVB-H is a derivative of the main DVB Terrestrial (DVBT)
format, which includes a number of features targeted at delivering content to
mobile devices.

To minimize power consumption in a DVB-H receiver, the information sent
to the handheld device is time-sliced. That is, it is delivered in concentrated bursts
so the receiver is not switched on all the time. This reduces power consumption by
up to 95 percent compared to DVB-T. In addition, the DVB-H standard includes
a number of features aimed at supporting user mobility, such as seamless handovers
between DVB transmitters. The signal format is able to accommodate users moving
at several hundred kilometers per hour.

Mobile Operating Systems

2007-07-04T01:01:00.000-07:00

The role of an operating system (OS) within a handset or handheld device is no different
than the OS deployed in computing terminals; the major differences in the
OS between the two environments are the result of handset constraints.

The OS is responsible for a range of tasks, which include management of the
processor, memory, and devices. Processor management determines
when an application can use the central processor and how to manage the resources
when multiple processes have to operate simultaneously. Memory management
allocates memory to processes so that they do not overlap and controls the reading
and writing of data to memory locations. Additionally, the OS will look after storage
of data, perhaps on a card or even a disk, and will also manage devices, or the
input/output (I/O) capabilities. The user interface (UI) is considered part of the OS
although not all OS include a UI that allows licensees to customize a UI to their
own design.

Operating above the OS will in most cases be a series of applications; and to
support these, the OS will have an application programming interface (API), which
abstracts the functionality of the OS for application developers.

In the context of a mobile handset, an OS has a set of limitations placed on it
that are the result of the processor capabilities and limited memory. Therefore, the
OS in these cases needs a very small footprint, which means very efficient code
writing. There are broadly two approaches to writing an OS for mobiles. The first
is to develop an OS from the ground up, specifically for the mobile environment.
The second is to take an OS that is perhaps used in desktop devices and produce a
compact version.

One critical area for mobile OS coders is reliability. The end user of a mobile
device would not tolerate systems crashes and lockups. This means not only reliability,
but also robustness as the underlying connectivity between the device and
the network is error-prone.

The range of handset OSs in today’s market includes completely closed or proprietary
systems through to open platforms (Figure 4.50). There are many variants
in between these two ends of the scale, where developers are able to create content
for a particular OS without having to know its technical details.

Proprietary Operating Systems
Many handset products have an OS that is proprietary, and in many cases the
details of the OS are unavailable, even perhaps to developers. However, the popularity
of smart phones, with comprehensive operating systems, and a recognition
that content developers can generate revenues for carriers, has meant that even
proprietary OS have a degree of openness associated with them.

For example, a proprietary OS will often include Java functionality, which
offers developers a route to content production through standardized, well-published
APIs; meanwhile, the core of the OS that drives the phone functionality
remains hidden. Handset vendors that have moved along this path will generally
offer developer platforms, software development kits (SDKs) and training, documentation,
and support options

Universal Serial Bus (USB), Bluetooth, Bluetooth Profiles

2007-07-04T00:59:00.000-07:00

The USB initiative was an attempt by the IT industry to provide a simple, standardized
interface that could support many applications and was capable of plugand-
play operation. The outcome of this was the definition of the USB connection.
There are two major versions of USB: version 1.1, which supports
data rates of 1.5 Mbps (low-speed) and 12 Mbps (full-speed), was supplemented
recently by USB version 2.0, which supports 480 Mbps (high-speed).
USB is electrically and mechanically a very simple interface with data lines
and power connections that allows a USB host device to provide power to connected
devices. Although the USB standard has been modified over time to include
the possibility of USB ports on mobile phones and similar devices, many handset
vendors depart from the USB standard when it comes to the physical connection
of USB on the phone.

The standard USB connection is too large for mobile devices; and although a
small form-factor version is now in the standard, many handset vendors choose to
use a proprietary physical connection for the USB on their handset ranges. This
means that end users will require a manufacturer-specific cable to connect their
handsets to other USB devices.

Commonly, the USB port found on handsets operates at full-speed (12 Mbps),
with the handset acting as a USB device; some handsets support version 1.1 whereas

Bluetooth
Bluetooth is a radio-based connection option that aims to solve some of the issues
addressed by IrDA, in particular the number of different cables that users require
to interconnect the multitude of terminals they own.

To overcome some of the limitations of IrDA, Bluetooth operates in the 2.4-
GHz, Industrial, Scientific and Medical (ISM) band. The advantage
of this band is that it is license exempt, which means radio equipment operating in
this band can do so without users requiring operating licenses. However, to support
the coexistence of many radio applications in the band, it is regulated in terms of
usable power levels and spectrum parameters.

Bluetooth was developed by the telecommunications industry, so the initial focus
of the standard was to provide a means for mobile handsets to interconnect with
associated devices, such as headsets, PDAs, and laptop computers. However, because
of its ready availability, Bluetooth is finding its way into other consumer products.
The Bluetooth radio component operates across up to 79 channels in the 2.4-
GHz band and, to mitigate interference, frequency hops around these channels at
a rate of 1600 hops per second. It should be noted that the full range of Bluetooth
channels is not available in all countries because of local regulatory constraints. The
power classes defined for Bluetooth devices support typical ranges up to 10 meters,
although the class 1 devices at 20 dBm can achieve ranges greater than 100 meters.
more recent handsets support version 2.0.

Bluetooth Profiles
As the Bluetooth specifications were written, it became obvious that there were
numerous real-world applications for the technology and that it would be unrealistic
to include each and every one of these in the standards. Therefore, Bluetooth
is based on the concept of a series of defined profiles, where a profile specifies how
the Bluetooth protocols should operate to provide a set of functions. The profiles
can be viewed as a series of building blocks from which real applications can be
constructed. New profiles can be added to the Bluetooth standard after completing
an agreement process.

An example of the relationship between a usage model and profiles is the 3-
in-1 phone. The 3-in-1 phone has three operational modes: (1) it is able to act as a
normal mobile handset and access the cellular network; (2) it can use Bluetooth to
access a gateway device attached to a landline (therefore acting as a cordless phone);
and (3) it is able to connect directly to other handsets using Bluetooth (therefore
acting as an intercom device). This usage model is based on two Bluetooth profiles:
(1) the Cordless Telephony Profile (CTP) and (2) the Intercom Profile (IP)
Outside the profiles that support applications, there are two generic Bluetooth
profiles, known as the Generic Access Profile (GAP) and the Service Discovery
Application Profile (SDAP).

GAP concerns the discovery procedures that allow Bluetooth devices to find
one another, and includes functions for establishing a Bluetooth connection and
optionally adding security. SDAP is used by one Bluetooth device to discover what
services are offered by a remote Bluetooth device.

Although there are a number of WLAN standards on the market, the dominant
series are those produced by the Institute of Electrical and Electronic Engineers
(IEEE). The IEEE project 802 oversees standards for all LAN technologies,
both wired and wireless, and the working group 802.11 is responsible for WLAN
standards. IEEE 802.11 has defined three radio technologies for WLAN, known
as 802.11b, 802.11a, and 802.11g, and Draft 802.11n. These differ in terms of the
data rates they support and the spectrum band in which they operate. Two of the
WLAN standards are designed to operate in the 2.4-GHz ISM band, while the
third, 802.11a, operates in bands around 5 GHz.

The preexistence of radar systems at 5 GHz in Europe means that 802.11a systems
cannot be deployed in this region without suitable modification. Additional
interference mitigation techniques were added by the 802.11h standard, which
adapted 802.11a radio for use under European regulations.

The term “WiFi” (wireless fidelity) is often applied to 802.11 systems. WiFi is actually
a brand name that belongs to an industry association, the WiFi Alliance, whose role
is to test interoperability of WLAN products. Any device that carries the
WiFi mark will have been tested against a baseline implementation of the standards
and has been demonstrated to operate with products from other manufacturers.

Video Coding

2007-07-04T00:54:00.000-07:00

Although reducing the number of pixels in an image reduces the bit rate of a video
signal quite dramatically, further reductions are necessary if video is to be supported
over the limited bandwidth channels of a cellular network. For most applications,
the number of frames per second can also be reduced from the standard 50
or 60 frames per second used in broadcast systems to a figure between 10 and 30
frames per second. Frame rates as low as 10 frames per second will be acceptable for
some applications, such as videoconferencing or videocalling.

Further reductions in bit rate are achieved by employing coding or compression
techniques. Although there are a number of techniques on the market for processing
video, they have similarities in terms of concept, using a combination of spatial and
temporal compression (Figure 4.36). Spatial compression techniques analyze redundancy
within a frame, produced for example by a large number of adjacent pixels all
having the same or similar levels of brightness (luminance) and color (chrominance).
This redundancy can then be removed by coding. In a similar fashion, temporal
compression looks for redundancy between adjacent frames; this is often the result
of an image background, for example, that does not change significantly between
one frame and the next. Again, this redundancy can be removed by coding.
As the power of electronic processors, particularly digital signal processors
(DSPs), has improved, video codecs have been designed that are able to offer equivalent
quality to their predecessors but at reduced bit rates.

Coding for still images is based on the same spatial compression as used for
video; there is no need to apply temporal compression to a single image. However,
the different still image formats are better suited to one type of image or another.
For example, JPEG works well with black and white or color natural images (such
as photographs), whereas GIF works better for black and white images that contain
lines and blocks (such as cartoons).

There is also a distinction between coding that is lossy and coding that is lossless.
The video coding techniques described here and JPEG for still images are all
classified as lossy in that they remove information through coding that cannot be
regenerated later. On the other hand, GIF is a lossless coding technique and subsequently
does not remove information through its coding.

Video Coding Standards
A number of video coding standards exist in commercial applications and two
main groups have worked on these standards: (1) the International Standards Organization
(ISO) and (2) the International Telecommunication Union – Telecommunications
branch (ITU-T). The ISO is responsible for the Moving Pictures Expert
Group (MPEG) that has produced a series of video coding systems (Figure 4.37).
The first MPEG standard, MPEG-1, was released in 1992 and was aimed at
providing acceptable, but sub-broadcast, quality video that could be used for CDs
and games. The video coding produced an output at 150 kbps. The audio coding
portion of the MPEG-1 standard included three coding options offering progressively
greater compression rates for the audio component. The third of these
options, MPEG-1 Layer 3 or simply MP3, has become a dominant standard for the
distribution of music and audio over the Internet.

In 1994, MPEG-2 was released, and offered improvements on the MPEG-1
standard. MPEG-2 can work at a variety of bit rates, but at 1 to 3 Mbps outperforms
the quality of MPEG-1. MPEG-2 is used for digital versatile disks (DVDs)
and digital video broadcast (DVB), and includes a range of audio coding options
such as advanced audio coding (AAC).

The most recent addition to the MPEG family, MPEG-4 was originally designed
for low bit services, with channels operating sub-64 kbps but can also be employed at
high bit rates into the Mbps range. The design intention was to provide video coding
for some of the “new” applications that were appearing, such as streaming services

Handset Sound Capabilities

2007-07-04T00:53:00.000-07:00

Handsets need audio coders and decoders for a variety of reasons, the most fundamental
being the encoding and decoding of human speech for telephony services.
However, with a typical handset now supporting multimedia functions, the sound
capabilities will support music, the audio that accompanies a video clip, and applications
such as games and ringtones.

Ringtones
Ringtones have become big business as users attempt to differentiate their handset
models from all identical models. The ringtone represents an easy route to phone
personalization. There are numerous formats (Figure 4.28) in which to provide
ringtones, and this represents the dramatic changes in capability from the very
early phones, which could only support monophonic tones, to the devices of today,
which are able to support complex music files coded with the same techniques used
to record CDs.

Some of the ringtone formats that have appeared in the marketplace are proprietary
and are perhaps only supported by a limited range of models from one
supplier or a small number of suppliers.

Ringtone Formats
Many early handsets had very limited capability in terms of ringtone support —
the tone output was monophonic as the sound elements could only play one note at
any moment in time. The manufacturer would maybe supply a handful of built-in
ringtones for the user to choose from, and there was no capability for downloading
new tones. Monophonic tones have a very artificial sound to them.

Increased capability brought polyphonic ringtones to handsets and, combined
with features and services that allowed users to download new tones on their
phones, the market for ringtones was created. There are a number of polyphonic
ringtone formats (see Table 4.2), including the Musical Instrument Digital Interface
(MIDI). MIDI differs from the other tone formats in that the MIDI file does
not actually contain coded music, but rather a set of instructions about the notes
to be played, the voice to be used for each note, and the duration and depth of each
note. The consequence is that MIDI files are very compact and therefore ideally
suited to ringtone downloads.

An improvement on MIDI is Scalable Polyphonic MIDI, which allows the same
content to be played on devices that differ in terms of their polyphonic capability.

A low-end phone might only have four-note polyphony while a high-end phone
might have 32-note polyphony; the same file could play on both handsets through
a process of scaling.

The eXtensible Music Format (XMF) was introduced to overcome the limitations
of the 128 fixed instrument pallet of MIDI. XMF allows downloading of new
sounds to replace the default MIDI sounds.
More recently, ringtones have been provided as MP3 files using the same audio
coding techniques used for music distribution. These files offer much more realistic
sound capabilities, and the availability of chart music as ringtones is evidence of the
popularity of this format.

There are a number of manufacturer-specific ringtone formats in use and also
formats devised by third parties; for example, the polyphonic Synthetic music
Mobile Application Format (SMAF) from Yamaha is supported on a range of
phones from different manufacturers.

Audio Coding
As with ringtones, handsets must be capable of supporting a wide range of audio
formats if an end user wants to decode audio from a variety of sources. There are
two distinct families of audio coder found in handsets. The first family is related
to the need to code the human voice for telephony services, although some of the
coders used are derivatives that support signals with a wider bandwidth than speech
(e.g., music). The second family of coders consists of those that comprise the audio
layer used in video coding techniques.

GSM handsets were originally built around the Full-Rate (FR) codec, which
was later supplemented by the Half-Rate (HR) codec, the Enhanced Full-Rate
(EFR) codec, and the Enhanced Half-Rate (EHR) codec (Figure 4.29). All these
coding mechanisms are built around a model of the human voice and, therefore,
while they offer good quality for speech, they are not optimized for non-speech
signals such as music.

The GSM specifications moved on to an Adaptive Multi-Rate (AMR) codec
that was also adopted as the standard by 3GPP for UMTS networks. This codec
could switch rates according to needs and conditions, but was still speech oriented.
However, recent improvements have been made to the codec, first by improving
quality, and second by extending the audio bandwidth and adding stereo capability.
Thus, the codec has evolved to support not only voice, but also high-quality
audio, including stereo music.

The second family of codecs found in handsets is based on the Advanced Audio
Codec (AAC) taken from the MPEG specifications. As with the AMR codec, the
AAC codec has evolved to improve quality and support stereo signals.

Display Technologies

2007-07-04T00:50:00.000-07:00

The displays used in handsets are based on liquid crystal diode (LCD) technology
that has been used in consumer products for some time. Liquid crystal materials
have some special properties that are exploited to create displays; most importantly,
the crystals have a twisted structure and the amount of twist can be altered by
applying a voltage to the crystal material.

LCD Display Structure
A basic LCD display is a sandwich of layers through which light passes.
One of these layers is the liquid crystal that is situated between two layers of glass
that contain electrical connections. By altering the signal to these connections, the
crystals can be made to alter their twist, which has an effect on the polarization of
the light and can be used to create the dark/light contrast necessary for a display.
The specific LCD technology found in many displays is super twisted nematic
(STN), which relates to the special form of liquid crystal that is used. Displays can
be characterized as being either reflective or transmissive. A reflective display relies
on incident light from the front of the display, passing through all the layers to a final
reflective layer where it is reflected back to the front of the display. It is possible to
provide front-lighting or back-lighting to reflective displays. A transmissive display
uses backlight from within the display. The use of back- or front-lighting will increase
the energy consumption of the display; and when used in handsets, the lighting has
an associated sleep circuit to switch off the light after a few seconds of user inactivity.
There are a number of variants of the twisted nematic (TN) display, although
they all generally employ the same principles of operation.

Color Displays
Adding color to a display is relatively simple. Each pixel in the display
has three separate filters associated with it: one red, one green, and one blue.
Therefore, each pixel is effectively divided into three sub-pixels. The filters can be
activated so that only light of a particular color can pass through for that pixel. The
three sub-pixels can be manipulated to create a range of colors.

Display Types
The way pixels in a display are addressed, so that they can be switched between states,
has led to two main display technologies, the so-called passive and active displays.
In a super-twisted nematic display, a passive display (often called STN,
the individual pixels are addressed by row and by column signals, one
pixel at a time, and thus the display is relatively slow because it takes time to build
up an image pixel by pixel.

On the other hand, active displays add another component in the form of a
transparent transistor at each pixel, hence these displays are referred to as thin film
transistor (TFT). Using the active technology allows a whole row (or column) of
pixels to be addressed at once, which means that creating an image is much more
rapid than in an STN display.

The disadvantages of STN displays are their relatively slow operation, and
there are also issues relating to brightness and angle of view. However, they are
cheap to manufacture and use less energy than a TFT display,
which corrects the major problems of the STN format. In handsets with two
displays, where a simple display is used for phone functions and a higher specification
display is used for viewing videos and playing games, it is common to
find both technologies deployed — STN for the simple display and TFT for the
high-quality display.

Other display technologies are being developed; one in particular, the organic
LED (OLED), is receiving a lot of interest. OLED are emissive devices and thus
do not require a backlight, they can also be created on very thin layers of polymer
(almost like printing), and they consume much less energy than LCD displays,
which makes them ideal for handsets and other power-constrained devices.
OLEDs are being demonstrated in consumer products and much research is
being conducted into these components to overcome some of their limitations, at
which point widespread deployment would become a reality. For example, the lifespan
of blue OLED elements is only a few thousand hours, which means their use
in a TV or phone display is not yet commercially possible.

Types of Mobile Terminal Memory

2007-07-04T00:48:00.000-07:00

Mobile handsets have always required elements of memory and storage as somewhere
for the operating system code to reside and execute. In early
phones, the user may have had access to a very limited area of memory to store contacts,
as an alternative to storing these on the subscriber identity module (SIM).

The increase in volume of applications such as messaging and the ability for
modern phones to support multimedia has increased the demands for storage
capacity within the handset. A typical handset contains a range of memory or storage
elements, which typically include the SIM card, hardware memory elements,
removable cards or memory sticks, and, most recently, hard disk drives.
With users now storing pictures, videos, music, and games on their handsets,
the total storage requirement has risen very rapidly; combined with this is the
increased complexity of multimedia signal processing, placing additional demands
on memory requirements.

Handset Hardware Memory
In common with any processing platform, a mobile handset requires a number of
different memory types to support its processing sequences. The two broad categories
of memory are Random Access Memory (RAM), which is as a working area
and as memory for user and application data storage; the other type of memory is
used to store the main program code and other applications. RAM is volatile and
will lose its contents unless power is maintained, whereas the E2PROM or Flash
memory used for the code storage is nonvolatile.

The RAM types found in mobile handsets include Static RAM (SRAM) and
Dynamic RAM (DRAM). SRAM will hold its contents as long as power is maintained
and, unlike DRAM, does not require refreshment on a regular basis. DRAM
memory stores bits of data as a charge on a capacitor; this charge must be regularly
topped up to avoid it leaking away.

Electronically Erasable Programmable Read-Only Memory (EEPROM or
E2PROM) is a nonvolatile memory type that can be programmed and reprogrammed
many times by means of electrical signals. E2PROMs have life cycles of
between 100,000 and 10 million write operations, although they may be read any
number of times. A limitation of E2PROM devices is that only one memory location
can be written to at any one time, this can be overcome by using Flash memory
devices, which can have a number of locations written in one operation.

The amount of hardware memory in handsets has increased considerably in
recent years as phones have included evermore complex operating systems and
applications, and also as users have required more memory for storing personal
data and multimedia files.

At the low end, the amount of E2PROM or Flash memory required might be
16 MB with an additional 8 MB of SRAM or DRAM. In addition, even low-end
phones might offer users memory of between 5 and 20 MB.
The manufacturing requirement to get more and more memory in a handset,
while at the same time decreasing the size of the device, has led to new techniques
such as multi-chip packaging (MCP) where one physical chip package houses both
SRAM and Flash.

Memory Growth
Driven by multimedia applications, the amount of hardware memory in handsets
has increased dramatically from the relatively small amount in voice-centric handsets
to a total of between 500 MB and 1 GB in 3G devices. The memory is typically
a mixture of RAM and Flash.

Until recently there were two main types of Flash memory in production, and
both of these are encountered in handsets; they differ in regard to the type of logic gate
deployed in the memory matrix — either NOR or NAND. However, hybrid Flash
memory devices are now appearing in the marketplace that combine the best features
of the two memory types, and these may soon find their way into mobile products.
NOR Flash was developed first; and while it is a true random access memory
(any location can be addressed when necessary), it suffers from relatively slow write
and erase times and a more limited lifespan than NAND Flash, which is both faster
and cheaper.

Memory Cards
Driven by appliances such as digital cameras, a number of removable data storage
formats have been invented, some of which are also deployed in mobile phones.
These memory cards or sticks can be used to store music, pictures, videos, and
games, which might have been downloaded or, in the case of pictures and videos,
captured by the user with the handset camera.

These memory devices are intentionally small, often a few tens of millimeters
square, and weigh only a few grams. Their storage capability however might be up
to several gigabytes. Typically, these devices are based on Flash technology and are
housed within the handset in a manner similar to the SIM.

Handset Processing, Processor Architectures, Coprocessors

2007-07-04T00:47:00.000-07:00

As handsets have evolved from simple voice-only analog phones through to complex
3G multimedia platforms, an increasing processing load has been assumed of
the devices. Processing loads and capabilities can be compared using the measurement
of “millions of instructions per second” (MIPS), and device manufacturers
will usually quote the MIPS value for processor chips.

The processing requirement for a 2G GSM phone is in the order of 10 MIPS,
with much of this processing requirement resulting from the voice coding function
(Figure 4.16). The addition of a 2.5G technology such as GPRS raises this figure
to somewhere on the order of 12 MIPS, although the processing complexity of a
2.5G phone will differ significantly across the range of device types encountered,
and may be as high as 40 MIPS.

A UMTS (W-CDMA) handset operating in a 3G network requires a total
processing capability in the region of 500 MIPS, with 40 percent of this requirement
resulting from the relative complexity of the air interface. Adding features,
particularly video processing, will increase the MIPS requirement and there is
already discussion of phones with 1000 MIPS (1 GigaMIP) requirements.
An issue for handset manufacturers and chip designers has always been the
processing limits of DSP chips, which is why handsets typically consist of multiple
processors and hardware accelerators (which remove some of the repetitive tasks
from the DSP and implement these in hardware).

Processor Architectures

The division of tasks between multiple processors within a handset is very common,
and a typical architecture would include a microprocessor (or microcontroller), a
DSP, and hardware accelerators. The role of the hardware accelerator is to remove
from the DSP the more routine repetitive tasks, such as radio channel processing,
leaving the DSP free to focus on other layer 1 tasks and vocoding (implementing a
compression algorithm particular to voice).

In this architecture, the hardware accelerator can be labeled as a coprocessor,
although this is a generic term that may have other meanings in the context of
handsets. Silicon manufacturers have in some cases produced single-chip solutions
that contain the three processing elements; this is an attempt to reduce the area,
volume, and cost of these vital handset components.

The typical task distribution in today’s handsets places the emphasis on the
accelerators rather than the DSP. However, as DSP technology improves, more and
more of the total processing load could be assumed by the DSP, although of course
by that time the evolution of services may be placing even more demands on the
handset processors.

Coprocessors

The spread of processing load has led to a number of different strategies for the
use of coprocessors (Figure 4.18). For example, in a dual-mode 2G/3G phone, a
chip manufacturer might offer a main processor that is responsible for the 2G and
2.5G baseband functions and a companion chip that adds 3G baseband functions.
These two processors can then be coupled to their corresponding radio modules.
This solution is perhaps suited to a manufacturer that is looking to evolve a range
of 2G/2.5G to support 3G capability. The basic core design of the handset can be
reused and the 3G functions are added in parallel. Another possible solution is to
use one processor for all the digital baseband processing and to use a separate coprocessor
to handle specific tasks such as multimedia services.

Types of Handset and the Market

2007-07-04T00:44:00.000-07:00

Handset Segmentation
Segmentation of mobile handsets is usually based on technology, with a correlation
between technology and price; that is, the more complex or feature-rich the device,
the more expensive it tends to be. However, more recently, and for the foreseeable
future, alternative segmentation strategies have become increasingly important for
both vendors and operators. They both seek to segment handsets and their markets
in a variety of ways to cope with market trends and aid in the differentiation of
their products to attract and retain subscribers:

Technology.

Technology is the traditional handset segment. Handsets are
divided on a technical basis, with a direct correlation to pricing so that a
handset incorporating less of the latest technology is invariably cheaper in
the marketplace than one with greater technical prowess. This can now also
be applied to features on the phone, such as the number of megapixels on a
camera or the amount of storage capacity.

Lifestyle.

This is an increasingly ubiquitous segmentation strategy, reflecting
the growing importance of the end user in the value web. This involves
matching the functionality of a handset with the specific needs of the end–
user (e.g., youth or style).

Price.

This strategy is beginning to be used more, owing to the move into
developing markets where customer income is low. It is primarily based on
the cost to manufacture the handset and the customer market segment at
which it is aimed. It also includes customer purchase profiling.
Application specific. This segments the market by optimizing components of the
handset to focus on a specific application, such as games or music. It is not a
technology-hungry mode, as the handset design is quite flexible and is a comparatively
cheaper process because it eliminates many nonessential components.

Low-end phones.

The term “low-end handset” is used normally to describe those
mobile phones that support only basic voice and data services and perhaps do
not support many features such as color displays or cameras. These phones
are usually targeted at the new user and prepaid user markets. While these
phones are normally at the cheaper end of the market and have traditionally
not supported much in the way of advanced features, the effect of technology
trickle-down is beginning to be felt even in this market sector.

It is not unusual to find color screens, cameras, and even WAP-based Internet
access available on some handsets. Polyphonic ringtones are very popular across all
market sectors and a good revenue generator for the network operators; therefore, it
is in the interest of the operator to enable the downloading and playing of various
types of ringtones, even in the so-called low-end device market.

Also in this segment is the low-cost handset or ultra-low-cost handset. The
GSMA is encouraging handset vendors to address the developing market by producing
handsets at a very low price point, U.S.$40 to U.S.$50, for example. These
devices have very few features in an effort to keep manufacturing costs to the bare
minimum. Often, these devices will support only voice and text messaging and
perhaps a limited selection of preprogrammed, non-changeable ringtones. While
these handsets are designed to address the developing market to make mobile communication
more affordable to those people that have little disposable income, they
may also find a place in the senior (or “gray”) market.

Low-Feature Phones

Low-feature handsets are generally geared toward more mature users and the
replacement market. The main attraction of the mid-range handset is the more
advanced feature set, in comparison to a low-end phone. Designs are more ergonomic,
with shapes and keypads that are easy to hold and handle. Displays are generally bigger than those on low-end phones and are more likely to be color. The
graphics quality and user interface are also expected to be superior, and this segment
is most likely to see the first significant showing of tri-band handsets.

Music and Entertainment

Music entertainment handsets are generally equipped with a mobile music player
for MP3 and AAC files, stereo FM radio, digital recorder, and Flash memory. This
is an extremely popular market segment, largely due to the popularity of standalone
music players such as the Apple iPod. Several handset vendors have launched
mobile phones that address the music market directly. These players are often
shipped to the subscriber with some form of access to a music downloading site,
(e.g., iTunes). One challenge that faces the industry in this market sector is the issue
of copyright and digital rights management (DRM). For the service to be popular,
musical content must be easy to distribute and exchange between authorized music
sites and vendors, as well as between the consumers of the music. This, however,
is at odds with the management of the copyright holder’s rights to the content.
Industry bodies such as the Open Mobile Alliance (OMA) are working on methods
to resolve these issues.

Feature Phones

This segment encompasses devices with high-technology capabilities and a variety of
features but without harboring an advanced OS, which would put them into the smart
phone device category. This segment has many of the attributes assigned to lesser segments
and also incorporates advanced features such as video capture and playback,
music, expandable memory slot, high-resolution screen, and megapixel camera.

Smart Phones

The smart phone is generally defined as a converged device whose primary function
is that of a phone with added advanced computing capabilities or PDA functionality
with an advanced operating system (OS). The category was born out of the
amalgamation of mobile phones that offer PDA functionality with an advanced OS
and a PDA with a WWAN connection. Smart phone devices invariably have a large
color display, are inclined to have a larger form factor, and are feature-packed.
There are two primary types of smart phone. There are those that are mainly
rich media devices with advanced OS and computing functionality that are basically
mobile phones embedding a number of additional features outside the usual
ones found on PDAs, such as MP3, camera, MMS, games, Java, or e-mail. These
devices might be used in the business and corporate markets. At the higher end
of the smart phone market, the devices tend to be PDA computers with phone capabilities,
typically manufactured by handheld device vendors such as HP, PalmOne,
and Toshiba; these devices are aimed at the business professional.

Open Service Access

2007-07-04T00:43:00.000-07:00

The specification, design, and implementation of services in a telecommunications
network were at one time limited to a very small pool of programmers, as services
were normally written as additional software for network elements (e.g., switches).
Even the advent of Intelligent Networks (IN) did little to improve this situation,
as a service designer still needed an intimate knowledge of telecommunications
networks and protocols.

Open service access (OSA) is an attempt to provide a much more open, yet
secure, environment for service development by abstracting the network functions
into a high-level view and providing access to these functions by means of standard,
well-defined application programming interfaces (APIs) (Figure 4.12). The work
on what is now known by some as OSA was started by the Parlay Group, which
focused on the U.K. network of British Telecom (BT), which the regulator wanted
to open up to third-party service providers. The Parlay Group works on the APIs
and the model for service providers to access the network functions.
The OSA project of the 3GPP is now aligned with Parlay, and the names are
now interchangeable. The OSA consists of an API that exposes, in an abstract manner,
the service capabilities of the network. A service designer can manipulate these
service capabilities to build innovative services (e.g., a service based on the location
of a mobile device).

A major concern for network operators is security and the security of information;
therefore, the OSA gateway that supports service providers also includes
a framework element that is responsible for authenticating service providers and
authorizing what functions (and information) that provider is able to see. Using
standard network signaling protocols such as SS7-based protocols, the OSA gateway
is able to manipulate the network elements to achieve the functions of a particular
service, although the service designer is isolated from the detail of these
protocols. The service provider in an OSA environment could be either within the
network (i.e., the network operators themselves) or a trusted third party.
Live OSA-based mobile services are available in some networks, although the
end user will not be aware that this is how the service is provided. These services
include prepay, location services, virtual private networks (VPNs), and unified
messaging (UM).

Handset and Standards Bodies

2007-07-04T00:42:00.000-07:00

The large number of technologies incorporated in a handset is reflected in the fact
that the standards on which this technology is based emanate from a diverse range
of standards organizations and industry forums. From the perspective
of the core cellular functionality, the most significant standards bodies are the two
3G bodies, the Third Generation Partnership Project (3GPP) and the Third Generation
Partnership Project 2 (3GPP2).

3GPP is responsible for the UMTS standard and also assumes responsibility from
ETSI for the GSM standard on which UMTS is based. 3GPP2 is responsible for the
cdma2000 family of technologies, which includes the Evolution systems, 1xEV-DO
(1x Evolution Data Optimized) and 1 x EV-DV (1x Evolution Data and Voice).

Both 3GPP and 3GPP2 have very similar structures, and indeed members.
The two organizations are composed of organizational partners (OPs), which are
national or regional standards organizations such as ETSI or the Telecommunications
Industry Association (TIA). It is important to note that there are cooperative
links between the two bodies as there is a lot of crossover technology that does not
rely on the underlying network standards and can therefore be transferred.
In addition to the OPs, both the 3GPP and 3GPP2 have market representation
partners (MRPs) and observers who contribute to the standards processes.
The technologies covered by the two 3G bodies represent approximately 98 percent
of the global users of mobile or cellular networks. In addition to the 3GPP and
3GPP2 standards, many other organizations have a bearing on handset design and
functionality; these include:

The Internet Engineering Task Force (IETF)
The World Wide Web Consortium (W3C)
The Open Mobile Alliance (OMA)
The International Standards Organization (ISO)
The range of applicable standards in a handset is indicative of the convergence
between telecommunications, Internet technology, and broadcasting and
entertainment.

Inter-Network Roaming , Handset User Interfaces , Human Interfaces

2007-07-04T00:41:00.000-07:00

A critical feature of most mobile network standards has been the support of internetwork
roaming, where a subscriber to one network is able to use his phone on
another network. Roaming is represented by both a commercial agreement
between two network operators to accept roamers and to provide billing data
in an agreed format; it is also a technical issue where the handset must be capable
of operating on both networks.

The GSM and UMTS standards have always included roaming as a key aspect,
and phones sold to subscribers on one network should work on other networks using
the same technology. However, the roaming user may not always have access to the
same services when roaming and indeed the look and feel of the visited network may
be somewhat different from the home network. Recently, work has been undertaken
in the standards to minimize the difference seen by roamers across networks. This
gave rise to the concept of the virtual home environment (VHE), which is based on
Intelligent Network (IN) techniques and appropriate inter-network signaling.

The situation for some roamers is eased in some cases by the existence of agreements
between networks that allow a roamer to dial his normal shortcode for, say,
mailbox access, and for the networks to translate this number behind the scenes.
While this may not be based on the VHE standards, it does start to solve the issues
of look and feel.

Another factor aiding some roamers is the coalescence of the market around a
number of large global operators. Once a mobile network operator owns multiple networks,
it is clearly able to provide a consistent user experience across those networks.

Handset User Interfaces
Manufacturers often have entire teams or departments that are responsible for the
design and implementation of user interfaces (UI), as this aspect of handset design
is so critical. The complexity of handsets and the multitude of functions they contain
make the UI critical in influencing the user experience. The UI supported by a
device will depend largely on device capabilities and will range from a very simple
UI for voice-centric handsets to very complex icon-oriented UIs, maybe incorporating
touch-screen technology, for data-centric devices. The best UIs are of course
those that are largely intuitive and that make redundant the complex (and costly to
produce) user handbooks or operating manuals.

The dynamics of the market often come into conflict at the UI. The handset
manufacturer will have spent a lot of time and money designing the UI, only for the
network operator to insist in some cases that it be replaced, in whole or in part, with
an operator-specific UI. This area of UI customization is another area in which the
manufacturer must fight to preserve brand identity.

Human Interfaces
The issue of user-personalization is also influencing the UI; many end users want
in some way to personalize the UI so it gives more ready access to the features and
capabilities that they use most often. The human or user interface on handsets
consists of a number of elements, including the display, the keypad or keyboard,
the navigation keys, and any soft keys or hot keys. The precise configuration of the
UI is determined by a number of factors, such as the device type and manufacturer
preferences

Introduction to Handset Technologies

2007-07-04T00:39:00.000-07:00

The mobile handset, in terms of its design and functionality, must satisfy three distinct
sets of requirements . These relate to the network operators, the endusers,
and the handset vendors themselves. The requirements of the end user will often focus
on features and capabilities, and the overall ease of use (usability), and of course, the end user would like maximum functionality for minimum cost. Increasingly, the aesthetic
appeal of the handset is important as it evolves from the functional devices of
early handsets to fashion items that a user may wish to change every 12 to 18 months.
Although users often look for complex feature sets in handsets, research indicates that
a typical user frequently uses only 15 to 20 percent of the phone’s capabilities.
For a network operator the handset represents the front end of the network and
is the platform through which users gain access to the rich set of services offered.
This again means feature sets and capabilities, and the ease of use is critical. The
network operator is also very interested in handset cost because in many markets
the handset is still subsidized by the operators, and therefore they bear some of the
real handset costs.

Handset vendors are increasingly asked to provide evermore complex devices
that are smaller and lighter than their predecessors yet cost no more or even less.
The overall cost of the actual handset components is further complicated by the
issue of technology licensing. A current 3G phone will contain many noncellular
technologies, such as video codecs and picture compression algorithms, for which
a license fee is payable to third-party innovators. Another major issue for handset
vendors is brand maintenance; in the mind of the enduser, the phone may become
associated with the network and not the original handset manufacturer, and the
manufacturers expend a lot of effort in keeping their brand profile high.

The requirement to satisfy the sometimes-conflicting requirements of all parties
means that the market for handsets has inevitably fragmented in terms of device
capability and form factor. The devices produced for the prepay segment are very
different from those aimed at the high end of the market.

Original Equipment and Device Manufacturers
In the area of manufacturing — and mobile handsets are no exception — the topic
of original equipment manufacturers (OEMs) will normally surface. An OEM
is a manufacturing company that produces components or sometimes
complete pieces of equipment to the specifications and design of another company,
the value-added reseller (VAR).

The VAR will either take components from one or
more OEMs and integrate these into a system, or take an entire OEM assembly and
repackage it. The level of repackaging might be as basic as relabeling products to
adding greater value (e.g., software and other elements).

Batteries
The handset battery is an essential component and is one of the largest contributors
to the total weight and volume of the final product. It represents the balance
between the competing demands of supplying energy and being as light and small
as possible.

There are many processes within the mobile handset that are relatively energy
hungry. These include the radio circuits, the processing for voice and
multimedia signals, and the display. Various techniques are deployed both within
the handset and in the specifications of the radio technology that aim at reducing
energy consumption and therefore lengthening the life of the battery.

Although battery technology has come a long way since the early days of mobile
networks, it can take up to ten years for a battery technology to proceed from concept
to being fully commercially available.

Operational and Business Support Operational Support System (OSS)

2007-07-04T00:38:00.002-07:00

The Requirements
Support for the operational network must be comprehensive in terms of structure
and procedures, and also in terms of systems and software tools. Broadly speaking,
the requirement can be split into three main areas:
1. Network management deals with managing the operational network, including
infrastructure, maintenance, and fault handling. The requirement is wide ranging,
allowing the complete network to be viewed in overview, or detail, with network
elements being handled remotely to keep the network running smoothly.
2. The customer service system allows for effective customer relations, covering
areas such as new orders, billing queries, and technical issues. The requirement
is easy to identify, and systems could be dedicated to this role, or be
fully integrated within a wider operational support system. In either case, information
must be available to the customer service representatives, relying on
good data interfaces between related functions (for example, customer billing
records need to be available to the customer service representative).
3. Other requirements can be grouped under the heading of business management
and include sales and marketing functions, finance, personnel, and
logistics, and a wide range of others.

The Role of CAMEL

2007-07-04T00:38:00.001-07:00

CAMEL has been specified to allow operator-specific services (IN services) to be
provided for subscribers even while roaming abroad. The service control point
(SCP) is generally located in the home network, allowing serving network switches
to interact with it to provide the advanced services.
CAMEL is an acronym for Customized Applications for Mobile networks
Enhanced Logic, and has been specified to allow for the introduction of IN
services in mobile networks alongside both call control functions and mobility
management.
In the later phases of CAMEL, it also allows for the provision of advanced
services in support of GPRS, SMS, and supplementary services. The interfaces
required for CAMEL are standardized to a high degree, allowing network elements
from different networks to work together using the CAMEL Application
Part (CAP) message set of Signaling System Number 7 (SS7). An example CAMEL
procedure is shown in Figure 3.47 for clarity.
The aim is to allow Intelligent Network interactions with a service control point
located in the subscriber’s home network. CAMEL takes account of mobile originated,
mobile terminated, and mobile forwarding cases, and also allows for both
roaming and non-roaming cases.
Modifications at the MSC essentially give the switch the ability to recognize the
requirement for a CAMEL-based service and build the required messages for the
specified SCF. In addition, both the HLR and VLR must be modified to hold the
relevant CAMEL subscriber details.
CAMEL has been defined in different phases to allow a staged approach to
implementation. Each phase is a superset of the previous one. Not all networks will
be at the latest phase of CAMEL, or even support CAMEL at all — but in many
networks, CAMEL is used to support prepaid services.

Intelligent Networks and CAMEL

2007-07-04T00:36:00.000-07:00

Introduction to Intelligent Networks (INs)
Traditionally, switching equipment (telephone exchanges) would need upgrading
each time a new service was added to the network (Figure 3.42). In some networks,
the presence of hundreds or thousands of telephone exchanges meant that this was
a very long and labor-intensive task.

The concept of Intelligent Networks (INs) allows the service to be provided
within a central computer or service control point (Figures 3.43). Once the telephone
exchanges have been upgraded to include the IN features, no further upgrades are
required except for the updating of the tables that identify the IN triggers, such as
the 1-800- or 0800-digit string to identify the toll-free or freephone service.

These services are generally provided through service control points, which
translate the service-specific dialed numbers (an 800 number perhaps) into standard
numbers for routing to the actual destination (telephone) in the network.
The special number is the initial trigger for the telephone exchange to contact the
service control point, to translate the number, and to carry out special billing, such
as reverse charging or collect calls, or premium rate.

These early services were soon followed by further advanced services based on
the intelligence or control features within the service control point. Extra service
features such as interaction with the user allow further customization of services.
IN separates service intelligence and switching. This means that new services
can be quicker and cheaper to install, and that service creation and switching is
split into two markets, thereby increasing vendor competition.

Most IN, including GSM Phase 2+ networks, use SS7 (Signaling System Number
7) protocols to enable the switches (known as service switching points, or SSPs)
to communicate with databases known as service control points (SCPs). A standardized
set of SS7 messages known as INAP (Intelligent Network Application
Part) is used for interaction between the SSP and SCP.

The intelligent applications that control IN services are defined by the operator,
and are not themselves standardized. This means that IN offers a route to operator
differentiation, but also that in many cases the same services cannot be offered
outside the network of that operator.

Service Control Platforms
Service control platform (SCP) is the name given to a platform that is, in some way,
controlling services on a network, or in some cases, across network boundaries. One
of the main advantages in using an SCP within a network is that it significantly
reduces the upgrade costs within a network whenever a new service is introduced.

Control of supplementary services. These may include services such as conference
calls, advice on billing, and provision of call-back services such as ring
back when free. Supplementary services are seen as key revenue generators for
network operators.

Number translation services. In most modern networks it is possible to dial tollfree,
local or premium rate services. These are, in effect, virtual numbers that
have special tariffs. Number translation services (NTS) minimize the amount
of configuration required on the network when a new service is provided.

CAMEL (Customized Applications for Mobile Networks Enhanced Logic)
INs and Mobile Networks: The Problems
In fixed networks, the IN concept can be implemented in various ways.
In each case, however, the interfaces are confined within a single network, allowing
the defined procedures and information flows to be applied on an interface
with known and defined endpoints, and within hardware belonging to the single
network operator.

Testing is therefore more straightforward as each interface can be tested independently
and, in addition, non-standard procedures and information can be used
to satisfy particular problems (even if this is just a certain way of interpreting an
ambiguous part of the standards). The IN procedures have been specified to interwork
(mainly) with call control, hence a simple relationship exists between the two.
For mobile networks, the situation is more complex because roaming scenarios
require that equipment in more than one network is involved. Considering
all the roaming agreements each network will have in place, and the rapid change of each of these networks as new hardware (switches, etc.) is added, it is
impossible to test each individual interface that will likely be involved in an IN call,
or to interpret specifications in anything other than a single standard way.

The next big complication is that IN procedures need to interwork with call
control, mobility management functions, and the additional features of mobile
networks such as the General Packet Radio Service and the Short Message
Service. Finally, any announcements should be supported by special announcement
machines, the positioning of which needs careful thought. Location in the
home network provides ease of management, but an international call leg would
be needed to play announcements to roaming subscribers. Locating the announcement
machines in serving networks leads to a higher cost of hardware and increased
management costs, but reduced cost per call.

BREW (Binary Runtime Environment for Wireless)

2007-07-04T00:35:00.000-07:00

BREW is also seen as an ecosystem. It has been associated mainly with cdma-based
systems; however, technically, it is available for use with GSM/GPRS and UMTS
networks — that is, it is mobile technology agnostic.
BREW provides a whole range of features, applications, and services that can
be accessed by the user via the BREW software on the handset. BREW application
developers are provided with the development and testing tools they need to make
the applications available to the users. Operators benefit from a flexible system that
provides a platform for a variety of advanced services and features.
The BREW distribution system (BDS) is the network-based system that distributes
the content and applications.

Messaging Platforms

2007-07-04T00:33:00.000-07:00

Voicemail Platforms
While voicemail appears to be a very simple service to provide to customers,
the fact is that it is an extremely important platform for operators — especially in
terms of revenue generation.

First, any call that is answered by a voicemail announcement is technically
terminated. All of the networks involved in the delivery of the call will receive
revenue. Second, on receipt of a voicemail message, many users will return the call,
generating yet further revenue for the operators.

In many cases, basic voicemail services are provided free of charge or included
in the monthly tariff. However, operators can charge a premium for premium
voicemail services, where the user is able to keep messages stored for a longer
period. Combining voicemail with calling line ID, operators can provide a service
that allows the user to call the person who left the message by pressing a single
key.

Short Message Service SMS
SMS allows for the exchange of short alphanumeric messages between a mobile
station and an SMS service center (SMSC). The messages can be either mobile
terminated
(from SMSC to mobile) or mobile originated (from mobile to SMSC). Of
course, in most SMS interactions, the mobile originated service is followed almost
immediately by the mobile terminated service (of the same message, but different
users). Messages are limited to 160 characters (depending on the language used).

Mobile Terminated Point-to-Point
These messages are sent from an SM service center (Figure 3.37) to a mobile station.
Upon receipt of the message, the mobile station will return a confirmation to
the SM service center. The message may be received when the mobile is not being
used, or even while it is being used for a voice call.

Mobile Originated Point-to-Point
Here the message is from the mobile to the SM service center, and a confirmation of
receipt (not necessarily delivery) is given. The generally accepted problem of mobile
originated SMS is the inputting of the text to the phone, which can be a slow and
laborious process. One increasingly popular short-cut is to edit the message on a
computer, laptop, or PDA (personal digital assistant) and then transfer the message
to the phone. On mobile phones themselves, intelligent text recognition software is
becoming increasingly sophisticated.

Enhanced Messaging Service (EMS)
An extension of SMS, EMS allows ringtones, operator logos, and other simple visual
images and icons to be sent to compatible devices. Pictures, sounds, animation, and
text can be sent to a device in an integrated package. No modification of the SMSC
is necessary because EMS uses the User Data Header (UDH) that is already present
in SMS messages. However, EMS-compatible handsets are required. The EMS
standard is included as part of the standard 3GPP feature set.

SMS Cell Broadcast
The SMS cell broadcast service transmits the same message to all mobiles within
a particular cell (or group of cells). The message limit in this case is 93 characters,
and the mobile must be in idle mode to receive the message. No acknowledgment
of receipt is given. Cell broadcast does not generate revenue because broadcast messages,
which offer no confirmation of receipt, cannot be charged. They tend, therefore,
to be seen as a value-added feature to attract customers. Uses might include
advertising (e.g., other network features) or the broadcasting of PSTN local area
codes such that a mobile user is able to distinguish between local and long-distance
calls (tariffs may vary between the two).

The Multimedia Messaging Service (MMS)

MMS is a non-real-time service, often seen as a natural progression from the GSM
Short Message Service. Like SMS, messages can be stored before being forwarded
to the recipient whenever they are available or they request to see the message. It
combines different networks and integrates messaging systems that already exist in
these networks, for example, SMS in GSM and so-called “Instant Messaging” via
the Internet.

MMS is designed to support either standard e-mail addresses or standard ISDN
telephone numbers; and WAP (Wireless Application Protocol) development also
provides significant support for MMS.

The user terminal operates in the Multimedia Messaging Service Environment
(MMSE). MMSE provides the service elements such as delivery, storage, and
notification, which may be located in one network or distributed across different
networks.

The basis of connectivity between the networks is provided by IP (Internet Protocol)
and its associated set of messaging protocols, enabling compatibility between
2G and 3G wireless messaging and Internet messaging.

The Virtual Home Environment (VHE) Concept

2007-07-04T00:32:00.000-07:00

In the VHE , users are consistently presented with the same personalized
features, user interface, customization, and services — in whatever network
they are located, or terminal they may be using (assuming that capabilities in the
network and terminal exist).

In defining the VHE, it is useful to introduce the concept of the home environment.
This can be synonymous with the user’s home network and subscribed
services, but can also include other value-added service providers (VASPs), which
are accessed through this home network service provider. The home environment
provides (and controls) the personal service environment in association with the
user’s own personal profile.

The serving network describes the network to which the user is attached at
the time, and thus may be a network in which they are roaming (when traveling
abroad). In the VHE concept, this network should be invisible to the user, with services
transported seamlessly. It may be another mobile network, but could equally
also be applied to a fixed network, the Internet, etc., depending how the users
choose to access their services at any one time.

VHE also takes into account the possibility of value-added service providers, who
may be part of neither the home nor the serving environment. For example, a banking
service may be provided directly from a bank VASP. Users should still be able to
transparently access these services whether or not they are in their home network.
Location Platforms
3G systems (including UMTS) are designed from the outset to provide for accurate
location of user equipment (mobile handsets), and this allows for providing
advanced location-based services. The location information is collated and managed
by location platforms (primarily the serving mobile location center and the gateway
mobile location center). This information can then be accessed and used by the
service platform in a variety of different services.

In UMTS, the location determination can be achieved in three main ways (discussed
shortly), and may also be provided as part GSM or GPRS.

The location information can be used by the PLMN operator, emergency services,
value-added service providers, and for lawful interception by authorized
agencies. The PLMN could use location information for a variety of purposes,
including handover optimization. Emergency services can radically improve the
overall response time if automatic mobile terminal location is provided. Valueadded
services can be significantly enriched and in some cases enabled — for
example, downloading a map showing where the subscriber is and how to reach a
local address.

The quality of location information is defined in terms of horizontal accuracy
(10 to 100 meters, according to the application), vertical accuracy (up to 10 meters),
and response time (no delay, low delay, or delay-tolerant criteria). It can also be
defined by priority (e.g., emergency services have highest priority), time stamping
(vital for some applications such as lawful interception), security measures (to
ensure controlled access to user location information), and privacy.

The Open Service Architecture (OSA) Concept

2007-07-04T00:31:00.001-07:00

OSA defines an architecture to enable operators and third-party developers (e.g.,
value-added service providers (VASPs)) to make use of network functionality
through an open standardized interface (called an application programming interface
[API]). It provides applications with access to service capability servers, and
thus provides the “glue” between the applications and the service capabilities of the
network.

In this way, applications become independent of the network. But within the
network, features such as Intelligent Networks and CAMEL provide support for the
required services. The actual applications, however, can be executed in application
servers physically separated from the core network entities. They may be part of the
operator domain, or may be third-party applications. The OSA API is secure and
independent of vendor-specific solutions and programming languages, operating
systems, etc.

Software and Service Platform Requirements

2007-07-04T00:30:00.000-07:00

There is a whole range of service platforms required in modern networks. They
include platforms for value-added services (VAS), such as voicemail, Short Message
Service SMS), and Multimedia Message Service (MMS). They also include
mobility databases, including home and visitor location registers (both of which
play an important role in service provision for GSM, GPRS, and UMTS); generic
service platforms, such as service control points (used in Intelligent Networks) and
service nodes. Finally, they include content servers, which provide access to basic
and advanced information, graphics, pictures, music, and video.

With the reduction in the cost of a voice call, the service platforms are assuming
greater significance as a way of providing value-added services in an attempt to
maintain and increase the average revenue per user (ARPU). In networks that are
optimized for data, such as ADSL, GPRS, and UMTS/3G, they provide the main
mechanism to grow the number of subscribers and to increase revenue.

The user would either be using these advanced data networks as a bearer to
access content and services from an independent provider, or be directed by network
resources (network-provided service platforms) to a point in the network where the
service can be accessed (network-provided service platforms or third-party service
provider platforms).

Network operators would like their customers to access the operator-provided
content and services so that they can capture the ensuing revenue, but increasingly,
third-party service providers are seen as an integral part of the overall system. In
fact, work has been done within industry and standards bodies to provide standard
ways of connecting third-party providers to the network so they can be accessed by
customers. Examples of third-party content and services include information such
as movie schedules, restaurant opening times and locations, credit card payment for
calls, navigation system updates (traffic updates), etc.

Vendors
Provision of service platforms of whatever sort is considered big business. For some
vendors, it is seen as a secondary function, helping to make the core product (often
telephone exchanges and routers) more attractive in that an integrated solution
can be provided, with the subsequent reduction in administration, testing, and
required employee knowledge base. Some vendors are seen as specialists in the area,
relying on reputation, and above all on an excellent product (or product range).
Example equipment vendors include, but are not limited to:

Alcatel
Ericsson
LogicaCMG
Lucent
Nokia
Nortel
Telcordia
Capacity

Capacity issues for service platforms can be quite complex, with huge variations
in usage throughout the day (which can be expected and predicted), and in addition,
variations occurring as a result of specific applications. These variations in
demand could be triggered by advertising campaigns for certain content, televoting
(by standard circuit-switched call, or messaging, for example), or perhaps by world
events dictating mass network usage (New Year’s celebrations, as an example).
In all cases, the service must be effectively managed. This includes the service and
application handling itself, as well as any congestion condition. Any request for service
that is not satisfied directly results in lost revenue. In addition, if congestion is encountered,
and appropriate announcements or responses are not given to the customer,
they will be dissatisfied and reluctant to try later, again resulting in lost revenue.
One of the main requirements therefore is to balance the cost of equipment
against potential usage, taking into account lost revenue through congestion.
This is easier to achieve for some platforms than for others. For example, platforms
that primarily provide database applications (such as a home location register
in GSM) can be planned, with forecasts of subscriber growth allowing a steady
scale-up of network resources. A known history of usage patterns for the HLR on a
daily and seasonal basis can be catered for.

Other platforms are not so easy to plan. These are generally the service platforms
that support a range of services (or a single service) that are influenced by less
predictable variables. For example, a service control point (explained later) handling
a televoting service will hit congestion levels early (and remain there) if a vote that
had forecast to receive two million votes actually receives three million. Although
mechanisms do exist within the technology to handle the congestion, the lost revenue
is still a huge problem. In any case, scalability is a big factor in service platform
provision.

Upgrading the network must also be transparent to the customer, leading to
the requirement for a flexible architecture. This would allow one to view a single
functional entity in terms of access to the service, but with the functionality actually
provided by a number of physical entities (servers), as shown in Figure 3.31.
This gives the required flexibility and scalability, allowing the network to grow at a
planned rate, while ensuring that spare capacity is calculated to cater for peaks, but
not be so great that it is wasted investment.

Redundancy
Some services and applications may be more critical than others. The high revenue
services should be protected from congestion when a mass service scenario is
expected. In addition, services and applications can be very different, with widely
varying requirements.

For both of these reasons, it is usual for a network operator to implement a number
of different service and content platforms. Even when the platform is generic
(such as an Intelligent Network service control point), it would generally be the case
that different platforms would support different services. There may be a platform
for prepaid billing, one for dialed network services, one for fraud control, one for
mass calling type services, etc.

In reality, all of these chosen examples could be provided by a single platform but
common sense dictates otherwise. Having a single platform implemented for each
service would not be ideal either. First, capacity requirements may require more than
one platform, but the other compelling reason is that of resilience and redundancy.
Continued availability of any service, even under platform failure, is extremely
important; hence, it makes sense for a service to be available for use by the required
customers in at least two platforms. The platforms would ideally be sited in different
geographical locations

Radio Resources

2007-07-04T00:28:00.000-07:00

Radio Resource Procedures for GSM, GPRS, and EDGE
The general purpose of radio resource procedures is to establish, maintain, and
release radio connections. To be effective, the radio resource procedures are complex
and include the cell selection/reselection and handover procedures.

Radio Resource in Idle Mode
The mobile handset continuously monitors the system information broadcasts on
the broadcast channel, interpreting the information appropriately. This information
contains parameters such as the identity of the serving cell and information on
how to access the network.

Once the cell is selected, the mobile leaves the idle state to register its location with
the network. In the absence of any other activity, it then falls back to the idle mode, to
monitor the paging channel (to identify any incoming calls), updating its location as
required (periodically, or as location area or routing area boundaries are crossed).

Radio resource in idle mode:
Monitor system information broadcast (contains required information)
Cell selection
Cell reselection
Location registration and updating
Monitor paging channel
Radio Resource Connection Establishment

This is instigated from idle mode. The RRC connection request is sent from the
mobile to the network. This may be to make a call, transfer data, or update a location
or routing area. Once the connection is established, a confirmation is sent to
the mobile.

The mobile now moves into the connected state, sending a Radio Resource
Connection Setup Complete indication to the network on the dedicated channel that
has just been assigned.

Paging
For idle mode mobiles, paging is initiated over the required location area, or routing
area for incoming calls, or for session setup in the case of packet services. The
core network node (MSC / VLR or SGSN) initiates the paging procedure.

The paging message is broadcast using Radio Resource procedures on the paging
channel that each idle mode mobile monitors within the cell(s).

Other Radio Resource Procedures
Radio resource procedures are extremely comprehensive and cover a wide range of
requirements. Some of the procedures not dealt with here include:

Power control (uplink and downlink)
Handovers (can be extremely complex in UMTS/W-CDMA)
Connection release
Packet mode procedures
Radio Resource Procedures for UMTS (including HSDPA)

UMTS (Universal Mobile Telecommunication System) procedures follow the
general requirements for GSM and GPRS, except that the radio interface and
channel structure are more complex and therefore require more (and more complex)
procedures. This is also true for HSDPA (High-Speed Downlink Packet
Access), which is a specific implementation of W-CDMA used on the UMTS
radio interface.

The mobility management (MM) and connection management (CM) procedures
are essentially very similar to those discussed above, except that more options
are generally available with UMTS because of the multimedia-capable nature of
the connections. In fact, the procedures for the GSM family of technologies are
contained within a common set of documents (available through the Third Generation
Partnership Project [3GPP] Web site at www.3GPP.org).

The documents are arranged such that all procedures relating to MM and CM
will be in a single document, irrespective of access technology.

Radio resource (RR) management is where the main differences occur between
the technologies and, in this case, the procedures for UMTS (W-CDMA) are separated
from those for GSM, GPRS, and EDGE by the use of different documents
detailing the RR procedures.

First, the radio elements are known as the Node B, which is equivalent to
the BTS in GSM, GPRS, and EDGE, and the radio network controller (RNC),
which is equivalent to the BSC. The term “radio network subsystem” (RNS)
is used in place of the base station subsystem (BSS) used in GSM, GPRS, and
EDGE.

To illustrate just two of the major differences between UMTS (W-CDMA)
and GSM, GPRS, and EDGE, two procedures relating to radio resources (RR) are
described below.

Procedure Sequences

2007-07-04T00:27:00.000-07:00

For all cellular systems, each transaction (incoming or outgoing call, data session,
text message, etc.) carried out by the user requires a number of separate procedures
to occur in a set sequence. Each transaction will have its own unique requirements,
but the general sequence will usually be common to all transactions.

The general sequence used for the GSM family of technologies is shown in
At this stage, this sequence ignores the complex requirement for setting
up the radio resources. In reality, the radio resource procedures would occur
within the sequence shown at any point where there is a requirement to allocate,
change, or release radio connections.

Note that the standard sequence illustrates the required procedures in six identifiable
steps. This sequence is referred to as the elementary procedure. Before any
communication with the core network, there must be a radio connection in place.
The mobile must also identify the user to the network prior to any service request
being granted.

The first step in the sequence is the assignment of an appropriate channel, which
may be after a paging message has been received from the network in case of an
incoming call. This is followed by the mobile handset requesting the service that is
required, as well as the security procedures (authentication of the user, and ciphering
of the radio channel). Both security procedures are optional; and although
available in most networks, there are exceptions.

These mobility management procedures are used for establishing a mobility
management (MM) connection with the core network, including the authentication
of the user. Once complete, connection management (CM) procedures are used
to set up and manage the transaction itself, including establishing outgoing or
incoming calls, setting up and managing data sessions, or sending or receiving a
text message. Once complete, all relevant channels will be released.

The elementary procedures will be initiated while a handset is in idle mode,
requiring it to move into dedicated mode for the duration of the sequence, before
falling back to idle mode once the sequence is complete. If another transaction
is required while one is in progress, the mobile uses the existing MM procedures
already in place as the basis for the new transaction. For example, no further security
procedures, or even a paging message, will be required for a mobile that receives
a text message while in the middle of a voice call. For GPRS and UMTS packetdata
operation, similar considerations apply.

GPRS Connections

2007-07-04T00:26:00.002-07:00

To move information from content and application servers to the handset and vice
versa, a path through the network must be defined. This is achieved using the PDP
context procedure, where the handset, SGSN, and GGSN all store data relating to
this virtual connection (Figure 3.26).
The GGSN defines the gateway to the content — maybe the Internet, MMS
server, or a WAP gateway. The GGSN is identified by a special identity known as
the Access Point Name — effectively a URI (Universal Resource Indicator, as used
for Web pages, etc.).
Because billing and other administrative functions may be based on this
GGSN, it does not make sense in most instances to change this gateway dynamically.
Hence, even when a user is roaming abroad, the GGSN is usually located in
the subscriber’s home network, and a path is defined through the serving networkand an inter-PLMN backbone network (incorporating GPRS Roaming Exchanges
(GRX)), to the home network. The border gateways define the edge of the administratively
separate networks with associated firewalls.
An alternative arrangement may be that the SGSN and GGSN are located in the
same network. This would certainly be the case where the subscriber is attached via
the user’s home network, but may also be true, for example, where connection settings
in the handset for Internet access use a generic APN (access point name), shared by
different operators, allowing access to the nearest GGSN (in the serving network).
Using different procedures, the connection can be maintained. If necessary, the
PDP context information can be moved from SGSN to SGSN without having to
reestablish either the connection or the PDP context.

Making Calls

2007-07-04T00:26:00.001-07:00

Calls to Mobile Networks
Making a call to a mobile network involves keying in the called subscriber’s
MSISDN (mobile subscriber’s ISDN) number. This number routes the call to the
called subscriber’s home network via a gateway mobile switching center (GMSC).
Here, signaling interactions with the home location register (HLR) occur. The
HLR, in turn, interacts with the visitor location register at the mobile switching
center at which the called subscriber is currently registered.
Eventually, although it takes very little time, new routing information is sent
back to the GMSC to replace the subscriber’s MSISDN number. The new information
allows the call to be routed to the network in which the called subscriber is
currently registered and, more specifically, to the serving MSC (either at home or
abroad [roaming cases]).

Calls from Mobile Networks
For outgoing calls from a mobile network, the serving MSC acts as a local exchange
for the subscriber that is making the call — with the call being routed directly from
the serving MSC (rather than having to route back through the subscriber’s home
network if abroad).

In all cases, however, the call is in accordance with any service information
being held in the VLR (having been previously sent from the subscriber’s HLR
when first registering at this MSC). This may include such restrictions as call barring
or advanced interactions required for prepaid subscribers

WLAN and Mobile Networks

2007-07-04T00:23:00.000-07:00

The existing GPRS/GSM and newer 3G networks have for a long time offered data
services to their subscribers.
Original circuit-switching data at rates of 9.6 kbps do not allow a great deal
of flexibility and severely restrict the service and content that can be offered. The
advent of GPRS has improved this matter significantly. The packet-switching service
can offer much higher rates to the user and at the same time offer resource
efficiencies to the network operator. However, the data rates are still in the range 10
to 40 kbps. Even if EGDE is deployed in the network, the data rate will only be a
maximum of hundreds of kilobits per second. The advent of 3G networks improves
on this data rate, thus allowing a greater range of services to the users.

These data rates, no matter how impressive, are simply blown away by the rate
available through WiFi hotspots — where typical data rates can be as much a
2 Mbps. The obvious difference here is that the cellular networks are providing
wide area coverage for voice and data, whereas the WiFi service is limited to a very
specific place and does not yet offer mobility services. There may be advantages to
the cellular operators by allowing some form of interworking between the WiFi
systems and their own networks. It is likely that this can be achieved in several different
ways, depending on available technologies and potential agreements between
WiFi and cellular operators.

Some cellular operators have formed alliances with the WiFi service providers,
allowing the cellular subscriber access to the hotspots under the single mobile
subscription. Mobile phone manufacturers are already producing equipment that
supports the WiFi radio in multi-mode devices. This allows the phone itself to use
the WiFi hotspot for data download or even in some cases to make phone calls
using VoIP protocols.

In due course it may become common for the cellular operators themselves to
build and maintain their own WiFi infrastructure, connecting directly to the mobile
core network. Using mobile IP and a 3G core network, this offers users seamless
mobility between mobile networks and WiFi systems under a single subscription.
WiFi is illustrated as a stand-alone technology that connects
directly to the Internet, or as an integral part of the cellular operator’s network —
effectively providing alternative access. Note that IMS refers to the IP Multimedia
Subsystem that is designed to provide support for advanced multimedia services.

Synchronous Digital Hierarchy (SDH)

2007-07-03T22:11:00.000-07:00

Although it is a reliable system, PDH has a number of obvious shortcomings. When
designing the next generation of transmission systems, consideration was given to
overcoming these shortcomings. The Synchronous Digital Hierarchy (SDH) was
developed from the American SONET (Synchronous Optical Network) and is
designed to provide an effective, well-managed, reliable, and efficient system for use
with optical-fiber (high-bandwidth) links. It was developed to be compatible with
existing systems and can therefore carry PDH channels as well as other formats.
Although seen as an expensive option compared to the tried and trusted
PDH alternative, the advantages of SDH are well recognized, and SDH is now
the accepted standard for digital transmission around the world. SDH has many
advantages over PDH, most notably:

It is designed to get the best out of high-capacity fiber-optic cables.
It is compatible with many other accepted standards such as E1 and T1.
It has built-in network performance monitoring and management facilities.
It is compatible with both European and American standards.
SDH can multiplex together a variety of different digital signal types, including
those that are already multiplexed using PDH, or even SDH (Figure 2.53).
These signals are arranged by the system onto a standard frame, called a synchronous
transport module (STM), ready for transmission. The smallest of these is STM-1,
which operates at 155 Mbps. There are larger frames, denoted STM-x. The x merely
implies the number of STM-1 equivalents transmitted (systems can employ STM-
4, STM-16, STM-64, or even higher). The inputs are known as tributaries.

STM-1 is equivalent to 63 × E1 links, or 1890 telephone channels.
The common implementation throughout Europe is a 155.52-Mbps link (carrying
many multiplexed channels) in STM-1 (synchronous transfer module) format,
which can itself be multiplexed into higher capacity levels (mainly STM-4, STM-
16, STM-64). These signals are typically transmitted over optical fiber, although it
is possible to send STM-1 over modest distances using coaxial cable or radio.

SDH Network Operation
Every voice or data channel is identifiable in the STM-x and allows selective demultiplexing.
This has the advantage of eliminating the multiplexer mountains of
PDH and allows new network structures beyond simple point-to-point connections.
This also allows some or all of the channels to be effectively protected in
case of a network failure. The ability to automatically protect traffic is an inherent
feature of SDH.

SDH has inherent management capabilities built into its structure. It is possible
to control and configure an entire network remotely. This has given rise to large
NOCs (network operation centers) where an operator can monitor, identify, and
react to any fault in a network within minutes.

Protection and management systems work best where the fiber optic (or other
medium on which SDH is running) is organized in ring structures to provide alternative
reconfigurable routes, and therefore more reliable connections for the user

Plesiochronous Digital Hierarchy (PDH)

2007-07-03T22:10:00.000-07:00

The PDH system effectively develops the idea of primary multiplexing using time
division multiplexing (TDM) to generate faster signals. This is done in stages by
first combining (multiplexing) E1 or T1 links into what are known as E2 or T2
links, and if required, going even further by combining (multiplexing) E2 or T2
links, etc.

This multiplexing hierarchy is known as the Plesiochronous Digital Hierarchy
(PDH). Plesiochronous, meaning “almost synchronous,” relates to the inputs that
can be of slightly varying speeds relative to each other and the system’s ability to
cope with the differences.

These groups of signals can be transmitted as an electrical signal over a coaxial
cable, as radio signals, or optically via fiber-optic systems. As such, PDH formed
the backbone of early optical networks.

The aggregate signal can be sent to line at any stage of the hierarchy, using the
appropriate transmission medium and modulation techniques.

PDH Network Operation — PDH network equipment is now quite physically
small, allowing for its deployment in locations other than a telephone exchange.

Network operators are able to house such equipment in street cabinets; enough
equipment to supply 120 telephone lines can be stored in an enclosure measuring
1.5 meter by 1 meter high. This has removed the need for many of the smaller telephone
exchange buildings that we used to see in fixed networks.

PDH systems are generally used only for point-to-point communications systems
because the signals must be fully demultiplexed to access a single information
channel. In addition, proprietary alarm configuration and management means that
equipment at either end of a PDH system must be from the same manufacturer.
PDH advantages include:

Equipment small enough for use in street cabinets
Good for point-to-point connections
Cost-effective support for access networks
PDH disadvantages include:
Manufacturer-specific systems
Multiplexer mountains
No integrated network management
Limited management available

Propagation, Attenuation, and Noise

2007-07-03T22:08:00.000-07:00

Propagation describes how a signal travels through a transmission medium (whether
metallic, radio, or optical). The signal energy will generally be confined within
bounded media (mainly cables), but radio signals can follow a variety of paths from
transmitter to receiver, including direct line of sight, reflected (from buildings or
terrain), or refracted (e.g., in layers of the atmosphere).

Attenuation describes the loss of energy as the signal travels through the medium,
resulting in reduced amplitude, while noise will be picked up from other sources of
electromagnetic energy, such as nearby cables or magnetic coils.
The noise levels picked up are usually very small, but the cumulative effect over
distance, together with the attenuation of the original signal, can quickly degrade
the channel to a point where it becomes unintelligible or large data errors occur.
High-bandwidth (usually high data rate) channels tend to degrade faster. Highfrequency
signals also tend to degrade relatively quickly.

Transmission systems are designed to minimize attenuation and provide good
immunity to noise. Fiber-optic cable is exceptionally good on both these counts
and has become the medium of choice for high data rate (high-bandwidth) channels,
especially in the core network.

Even for copper or radio systems, we can still mitigate the problems of attenuation
and noise on long transmission paths by careful system design, and also by
increasing transmitted power to compensate, or amplifying or regenerating the system
at appropriate points in the transmission link before it becomes unintelligible.

Amplifying an analog signal once it has attenuated and also picked up noise
would result in a larger-amplitude signal that also retains the amplified noise.
Whether this affects the user experience would depend on the proportion of noise
in the overall signal and the modulation scheme used.

As long as a digital signal can be regenerated before the noise makes it difficult
to recognize whether the bits are 1s or a 0s, the noise can be eliminated, and a clean
set of data can be retransmitted. Of course, some mistakes will inevitably occur
because of the random nature of the noise that is picked up, but these low levels
of bit errors can be eliminated or minimized by advanced digital processing techniques
in the receiver.

In general, the “noise immunity” that digital signals experience compared to
analog systems ultimately manifests itself in many ways, including clearer voice
channels, low error rate data channels, higher-capacity radio systems (for the same
infrastructure costs), or longer transmission paths.

Signaling and Control

2007-07-03T22:06:00.002-07:00

Control Requirements
To ensure the establishment of end-to-end connections with the required quality
of service, control information must be passed between users and the network,
and between network elements. This control information comes in many different
forms, both simple and complex. The information required in the control information
varies from system to system, and also at different points within the same
system. Control information is required to provide services of many types, not just
end-to-end connections. Control data in telecommunications networks has traditionally
been called signaling.

The Importance of Signaling Systems
Signaling systems are essential to the operation of any telecommunications system.
As switching and transmission systems have evolved, signaling systems have had
to develop continuously to support the services offered in modern telecommunications
networks.

Today, with truly global communications systems in place, signaling plays a
critical role. However, most users are unaware of the signal processing that takes
place even for a simple local telephone call. This is a long way from the early
systems where operators sitting in the local exchange performed most signaling
functions.

Functions of a Signaling System
A signaling system must be able to perform many functions within the network.
One of the most important functions is that of call setup, where the dialed digits
are transmitted across the network and the subsequent routing of the call to its
destination. Should the called party be engaged, this must be notified to the calling
party — who will normally hear this as a tone. When a call is completed, clear
down signals must be transmitted to both parties, and the transmission and switching
systems released.

When a normal telephone number is received by a telephone exchange, it can
use simple look-up tables, held locally, to route the call. However, in the case of
freephone or toll-free numbers, the exchange will have to access a regional or central
database to route the call. This will be achieved over signaling links, able to
interrogate and report back from the databases. This technique forms the basis of
Intelligent Network (IN) technology.

Without the ability to accurately and reliably transmit billing information across
and between networks, few network operators would stay in business for very long.
Another key area for signaling is for operation and maintenance purposes. Should it
be necessary to remove an inter-exchange trunk from service, this must be signaled
to a remote exchange so that it does not attempt to use the out-of-service circuit.

Access Signaling
Loop/Disconnect Signaling —The term “loop/disconnect” refers to a type of
signaling used within the local loop, whereby the telephone, fax machine, modem,
or other device sends signaling information to the local exchange (Figure 2.27). It
is so called because the system relies on connecting and disconnecting a loop across
the line, allowing an electrical current to flow between the two wires when the loop
is made. This current is detectable by circuitry in the telephone exchange.
Although not commonly used anymore for this purpose, loop/disconnect signaling
can be used for the transmission of the dialed digits. Each number is transmitted
as a corresponding number of breaks or disconnections in the local loop.
This form of dialing has a speed of ten pulses per second and consequently it takes
a long time to transmit national or international telephone numbers.
While loop/disconnect dialing is not often used, loop/disconnect signaling is
still used for the basic signaling requirements of the local exchange, where the telephone
signals to the exchange request to make a call (line seizure) and also when
the call is cleared down.

DTMF Signaling — Dual-tone multi-frequency (DTMF) signaling (Figure 2.28)
is now the preferred signaling method for the transmission of dialed digits. This
system works by representing each digit on the keypad with a combination of two
frequencies. These frequencies are audible to the caller. DTMF signaling has the
advantage of being much faster than loop/disconnect dialing. It also has the advantage
that the user, being able to hear the tones, is aware if a button press is missed
or accidentally repeated.

Circuit Switching, Packet Switching, and Message Switching

2007-07-03T22:06:00.001-07:00

Circuit Switching — In circuit-switched networks , a dedicated path
is set up between the two parties. This path remains for the exclusive use of both
parties for the duration of the call, and is therefore not available to any other users.
This method has traditionally been used within standard telephone exchanges and
networks since telephony was first developed.
There is a delay involved in setting up circuit-switched calls because each of the
switching nodes has to route the call. However, the actual delays encountered once
the connection has been established are minimal. This makes circuit switching
ideal for voice and other real-time applications.
Circuit switching can be inefficient in its use of network resources. During a
voice conversation there are periods when neither party is talking but the connection
is still tied up and unavailable for other users. Similarly, bursty data, which has
gaps between the data, is not efficiently carried over circuit-switching networks.
Charging for circuit-switched services is generally based on the duration of the
call. The PSTN and ISDN are examples where circuit switching is employed.
Packet Switching — Packet switching involves dividing the data into packets (or
cells or frames) prior to transmission. The length of the packets varies enormously,
depending on the technology employed.
Added to each packet is the destination address, together with other control
information. The packets are then transmitted across the network. This addressing
means there is no requirement to set up a pre-established link. To some extent, each
individual packet can be viewed as being able to find its own way to its destination.
In a packet-switched network (Figure 2.23), the resources are shared between
many users. This leads to more efficient use of these resources than provided for by
circuit-switching techniques. However, with packet switching there is a danger of
congestion occurring. The subsequent delays are both variable and unpredictable.
Much effort has been put into reducing these delays for applications that require
near-real-time transmission such as voice telephony.
When data is divided into packets, it does not follow that all the packets that
contain the original data will follow the same route to the destination. This can
order before delivery to the recipient. Examples of packet-switching technologies
include X25, FR (Frame Relay), ATM (Asynchronous Transfer Mode), and IP
(Internet Protocol).
Because it is possible to charge for data throughput rather than for the duration
of the connection within a packet-switched network, it is more feasible to have permanent
online connections than can be provided for by traditional circuit-switched
networks. Most commentators see packet switching as the future backbone of new
high-bandwidth telecommunications services.
Message Switching — It is not always necessary to establish an end-to-end circuit
for the transmission of data. So-called store and forward techniques can be
applied.
In Figure 2.24, an e-mail message is transmitted between nodes A and D.
Because no circuit is established, the message is carried in stages over the links
between the nodes. At each stage, the message is stored within the node while the
next link is established. This does lead to queuing delays at each stage; but to the
applications utilizing message switching, these small delays are unimportant.
Another example of the use of message switching is for SMS text messaging
within a GSM network (Figure 2.25.). When a user sends a text message, it is
transmitted across the air interface into nodes within the GSM network. The entire
message is stored within the node responsible for SMS messaging. Here, the message
is stored before it can be forwarded to its destination. Should a node be unable
to forward a message for any reason, it will retry until an expiry time or number of
attempts is reached. Depending on the application, a failure message can be transmitted
to the originating subscriber to inform them that the message transmission
has failed.

Transmission: Media and Systems

2007-07-03T22:03:00.000-07:00

The media needs to carry information, and to represent this information requires
a variation in the electrical or optical signal. This variation can take many different
forms, but is generally referred to as modulation, and can use analog or digital
techniques. Modulation is used to vary the electrical or optical signal to represent
information on transmission media.

A fundamental aspect of the transmission medium is the frequency at which it
is designed to work. This will differ from telecommunications system to telecommunications
system and can include multiple frequencies to provide for multiple
communication channels.

Radio systems such as GSM can have hundreds of frequencies specified for
use within a specified part of the frequency spectrum, whereas copper-based telephony
systems might only have a single frequency band specified for use. GSM
needs multiple frequencies to allow different frequencies to be used in different
geographical parts of the network (to avoid radio interference within the communication
channels), whereas copper wire physically separates the communication
channels. This illustrates the difference between unbounded and bounded media
(respectively).

Transmission systems are designed to organize the information in a way that
allows the equipment at either end of the media to work in unison. They provide a
scheme for coding and decoding the information such that one or more communication
channels can be identified (on the media, and at the specified frequency), and
include extra information so that the equipment can be effectively synchronized
and managed. If problems are experienced within the system, this can be notified
via specific alarm channels, allowing remedial action to commence.

Copper Twisted-Pair Cable
Although they are the oldest of the media types used in telecommunications, copper
cables remain the foundation of most national fixed telecommunications systems,
especially within the local loop between the customer’s premises and the local
telephone exchange.

Copper was chosen for its good conductivity, together with its price and flexibility.
There are metals that have better electrical conductivity properties, but most
are more expensive than copper. The requirement for early telephone circuits was
that the media should be capable of carrying low-bandwidth audio signals. The first
copper cables were paper insulated. Paper worked well as an insulator, but as the
number of cable pairs increased, the cables became extremely stiff due to internal
friction. In the 1950s, plastics were introduced as the insulating material, with lowdensity
polyethylene, high-density polyethylene, and polypropylene all being used.

Crosstalk is a phenomenon where signals intended for transmission on a circuit
are electrically induced into adjacent circuits, causing interference. This was a particular
problem of early cables. To reduce this, twists were introduced along each
pair of cables, with up to 25 unique twists being used within a 25-pair cable group,
each spaced at a different distance. It was assumed in the 1980s and 1990s that copper
was an old technology with a limited future. Telecommunications companies
planned ahead to install fiber and coaxial cable systems in the local loop. Eventually,
the cost of doing so was judged to be too high in most cases.

Today, new techniques have been developed to transmit higher data rates than
had previously been thought possible using copper wires with technologies such as
Asymmetric Digital Subscriber Line (ADSL). This means that telecommunications
companies have the opportunity to bring in revenue from high-speed data services
using the existing cable.

Copper Coaxial Cable
A variation of the use of copper is its application in coaxial cables (Figure 2.14).
Here, an inner conductor is first covered in an insulating material and then surrounded
by a wire mesh or metallic screen. The cable is so named because both the
inner conductor and the outer screen share the same axis. Coaxial cables are far
more tolerant of electrical noise than traditional copper pairs and are able to transmit
higher data rates. The use of coaxial cabling dramatically reduces crosstalk. The
main application for coaxial cables was to serve inter-exchange trunk connections
where a pair of cables is used for carrying multiple voice channels, one each for
the transmit and receive paths. Coaxial cabling is also used for so-called thin-wire
Ethernet connections. However, this system has the disadvantage that any failure
along the cable route will cause the entire network to fail.

Radio
Radio systems can be used to transmit signals from a few meters to several thousand
kilometers and can be used for both point-to-point and broadcasting applications.
Radio signals are a type of electromagnetic radiation, with similar properties
to light but with a much shorter wavelength. As with all electromagnetic radiation,
radio waves have both an electric and a magnetic field that travel at right angles
to each other. As the signal travels outward, it can be compared to a stone being
thrown into a pond. Much like the waves on a pond, radio waves get weaker the
further from the transmitter they are. In radio, this progressive weakening of the
signal is referred to as attenuation or path loss.
The frequency of a radio signal will determine how it can be transmitted. Lowerfrequency
signals, such as those in the very low frequency (VLF), low frequency (LF),
and medium frequency (MF) bands that cover frequencies up to about 2 MHz, can
propagate using surface or ground waves. As currents are induced in the Earth, this
has the effect of slowing down the part of the wave that is closest to the ground,
causing a “bending” of the wavefront around the surface of the Earth. Hence, these
lower frequencies can be transmitted either by line of sight or by surface waves. The
combined effect is termed “ground wave” .

Another method of radio propagation is by the use of sky waves.
Certain frequencies, including those in the high frequency (HF) band have the
property of being refracted by layers in the atmosphere known as the ionosphere
and troposphere. Essentially, when the signal reaches a heavily ionized layer, this
layer reflects the signal toward an area of lower ionization. This makes it possible to
send HF transmissions many thousands of miles around the globe. It is possible for
sky waves to propagate lower frequencies but in most cases these work only under
certain atmospheric conditions or at night.

At yet higher frequencies, such as those in the very high frequency (VHF), ultra
high frequency (UHF), and super high frequency (SHF) bands, most of the radio
signal is transmitted by direct waves. Although there is still some component of
ground- and sky-wave propagation, most of the signal relies on line-of-sight transmission.

As frequency increases, so path loss increases. This necessitates the use of highly
focused, directional antennas for microwave transmission such as that used in satellite
communications. One of the main advantages of radio transmission is that
it removes the need for expensive cable-laying activities, which can account for 50
percent of telecommunications infrastructure costs. Coupled with the recent progress
using the radio spectrum more efficiently has led to radio being heralded as one of the
most promising media types for the next generation of telecommunications services.

Optical Fiber
Although first proposed in 1966 by Kao and Hockham, it was only in 1970 that Maurer,
Keck, and Schultz designed and produced the first optical fiber that had characteristics
that made it suitable for use in telecommunications. Their work enabled the
production of fibers that had very little attenuation (loss of signal strength or intensity
in the cable), and which kept most of the light traveling through the cable.
An optical fiber has a very thin core of glass or silica surrounded by an outer
cladding made of a similar material, but with a lower refractive index.

Transmission Systems
Transmission systems are complex and involve many different aspects of information
transfer and managing that information. They refer fundamentally to the way
in which channels can be identified on the transmission medium, rather than the
way the application data is coded or any higher layer transport protocols/systems
(such as IP technology used to code Internet-type traffic).

Just about in all cases, the application data or transport protocols for any network
will require the final coding and synchronization that will allow the information
to be carried and identified within one or more specific channels on the
transmission medium (often at or around a specified “carrier” frequency). It is this
final coding process (and the additional features provided within the coding) that
defines the transmission system used.

Transmission

2007-07-03T22:01:00.000-07:00

The transmission medium can take many different forms, such as (1) copper wire,
which has been used since the early days of communication; (2) optical fiber, which
is a relatively new medium and is increasingly being used; and (3) radio, which also
has been used for many years. Each of these media can be bi-directional, that is,
allowing information to pass in both directions.

Copper may be limited by bandwidth, which limits the amount of information
that can be transmitted in a given time, compared to optical fiber, but its cost is
low. In contrast, optical fiber is relatively expensive but can carry more data in a
given time. Both copper wire and optical fiber cable are more reliable than radio,
but radio has many other advantages.

Radio transmission is a very versatile medium, ideally suited to a mobile environment,
but its bandwidth is extremely limited and therefore its total capacity is
limited. It can also be adversely affected by atmospheric conditions.

Speed of data transfer, error rates, and other key characteristics determine which
transmission medium will be used in particular circumstances. Information can be
represented in many different forms. To ensure compatibility across systems, standard
transmission systems and techniques have been specified in many instances.

Switching
To enable the placement of a call from the originator through the network and
on to its final destination, that call must pass through several switches or routers.
Switches or routers allow great flexibility in connecting transmission
resources. This gives rise to endless possibilities for end-to-end connections between
users. Users may be located nearby or be very remote, but the switches or routers
within the network will ensure that the information passes over the required transmission
resources to provide end-to-end connectivity.

The number of switches or routers needed in an end-to-end connection will
vary, and will depend on many factors, including network topology (the configuration
of the various elements), the geographical distance between the user terminals,
and the capacity of the switch or router and associated transmission media.

Signaling and Control
To ensure the establishment of end-to-end connections with the required quality
of service, control information must be passed between users and the network, and
between network elements. This control information comes in many
different forms, both simple and complex.

The information that must be included in the control information varies from
system to system, and also at different points within the same system. Control
information is required to provide services of many types, not just end-to-end connections.
Control data in telecommunications networks has traditionally been
called signaling.

Billing
Increasing network sophistication and a corresponding increase in service choices
and methods of service provision, have led to an increased requirement for flexible
and more complex billing systems. This is confusing for network operators and
customers alike, and a great deal of work is underway to provide choices that are
achievable, simple to implement, and, very importantly, reflect the requirements of
the customer. Service charges that are simple to understand, as well as flexible payment
options, are of increasing importance.

Telecommunications: A Definition

2007-07-03T22:00:00.000-07:00

The term “telecommunication” is derived from the Greek tele, meaning distant, and
communicate, meaning sharing. From the beginning of time, the need to communicate
has been part of man’s inherent being. The human race has, throughout the
years, communicated using different techniques, dependant on the circumstances
and available technology. Early forms of communication included:

Smoke signals of the early American Indians
Drums of African tribes
Semaphore using flags

Papyrus and paper used to record communication for later use
As time passed, technology advanced and it is now expected that telecommunications
is both reliable and efficient. Nothing is more annoying than having to
repeat your message to the recipient, whether by phone, facsimile, or e-mail. Other
areas that are now paramount to the customer are the availability and quality of
additional services that may be requested, and all this has to be at a price that keeps
both the customer and the seller happy.

Today, telecommunications can be defined as:
The reliable and efficient movement of information between two or
more points for the purpose of providing services of the required quality
and availability, at a price which reflects the needs of the customer
and the business.

Standards and Regulations

2007-07-03T21:56:00.000-07:00

In telecommunications, a standard is a document or specification that describes the
process by which information is transmitted or received. The standard generally
refers to the interface between two entities (e.g., the mobile phone and the base station).
A standard also describes the services in a telecommunications network and
the manner in which services should be supported.

Standard methods or products normally emerge as a result of commercial success
in the marketplace; a classic example always mentioned when discussing standards
is the VHS and Betamax videocassette formats. VHS became the industry standard
in this case as a result of market success. Letting the market decide on the standards
by this process may not always be the best and most efficient way, because there
must always be a loser. In the past, the telecom industry has used this method, but in
these days of global roaming, there are many more benefits to derive from the industry
making agreements about the methods and process of telecommunication.

All of the bodies described below are committees consisting of professionals
from manufacturers, network operators, service providers and others, where the
technical and non-technical issues of solving telecommunications problems are discussed.
In some cases, several solutions may be presented and a vote may take place
to decide on the best solution. In this way, all parties can agree and the winning
solution will be written up as a technical specification. GSM is a very good example
of the success of this method of determining telecom standards.

International Telecommunication Union (ITU)
The International Telecommunication Union (ITU), headquartered in Geneva,
Switzerland, is the United Nations’ specialized agency for telecommunications. The
main work of the ITU is divided among three sectors, namely:
1. The Radio Communication Sector (ITU-R)
2. The Development Sector (ITU-D)
3. The Telecommunication Standardization Sector (ITU-T)

The ITU-R coordinates matters dealing with radio communication services, radiofrequency
spectrum management, and wireless services. The ITU-D focuses on
technical assistance to developing countries and countries with economies in transition
to allow the development of telecommunications networks and services. The
ITU-T ensures the efficient and on-time production of high-quality standards covering
all fields of telecommunications on a worldwide basis, as well as defining tariff
and accounting principles for international telecommunications services.

European Telecommunications Standards Institute (ETSI)
The European Telecommunications Standards Institute (ETSI) is an independent,
non-profit organization, whose mission is to produce telecommunications standards
for today and for the future. Based in Sophia Antipolis (France), the ETSI is officially
responsible for standardization of Information and Communication Technologies
(ICT) within Europe. These technologies include telecommunications, broadcasting,
and related areas such as intelligent transportation and medical electronics.
The ETSI unites 688 members from 55 countries inside and outside Europe,
including manufacturers, network operators, administrations, service providers,
research bodies, and users — in fact, all the key players in the ICT arena.
The ETSI plays a major role in developing a wide range of standards and other
technical documentation as Europe’s contribution to worldwide ICT standardization.
This activity is supplemented by interoperability testing services and other
specialisms. The ETSI’s prime objective is to support global harmonization by providing
a forum in which all the key players can contribute actively. ETSI is officially
recognized by the European Commission and the European Free Trade Association
(EFTA) secretariat.

Third Generation Partnership Project (3GPP)
The 3GPP (Third Generation Partnership Project) is a collaborative agreement
established in December 1998. The collaboration agreement brings together a
number of telecommunications standards bodies known as “organizational partners.”
The current organizational partners include the ARIB, CCSA, ETSI, ATIS,
TTA, and TTC.

The establishment of 3GPP was formalized in December 1998 by signing “The
3rd Generation Partnership Project Agreement.”

The original scope of 3GPP was to produce globally applicable technical specifications
and technical reports for a 3G mobile system based on evolved GSM core
networks and the radio access technologies they support (i.e., Universal Terrestrial
Radio Access (UTRA), both frequency division duplex (FDD) and time division
duplex (TDD) modes). The scope was subsequently amended to include the maintenance
and development of the Global System for Mobile communication (GSM)
Technical Specifications and Technical Reports, including evolved radio access
technologies (e.g., General Packet Radio Service (GPRS) and Enhanced Data rates
for GSM Evolution (EDGE)).

Third Generation Partnership Project 2 (3GPP2)
The Third Generation Partnership Project 2 (3GPP2) is a collaborative third-generation
(3G) telecommunications specifications-setting project comprising North
American and Asian interests developing global specifications for ANSI/TIA/EIA-
41 Cellular Radio Telecommunication Intersystem Operations network evolution
to 3G and global specifications for the radio transmission technologies (RTT) supported
by ANSI/TIA/EIA-41.

3GPP2 was born out of the International Telecommunication Union’s (ITU)
International Mobile Telecommunications “IMT-2000” initiative, covering high
speed, broadband, and Internet Protocol (IP)-based mobile systems featuring
network-to-network interconnection, feature/service transparency, global roaming,
and seamless services independent of location. IMT-2000 is intended to bring
high-quality mobile multimedia telecommunications to a worldwide mass market
by achieving the goals of increasing the speed and ease of wireless communications,
responding to the problems faced by the increased demand to pass data via
telecommunications, and providing “anytime, anywhere” services.

UMTS Forum
The UMTS Forum was set up by a number of telecommunications operators, manufacturers,
national governments, and other organizations. Its aim is to define a
common strategy and policy for the development and implementation of the future
Universal Mobile Telecommunications System, combining personal communications
with multimedia services and applications built on existing fixed and mobile
infrastructures. It seeks to contribute to the development of a European policy
on mobile and personal communications, and provides advice and recommendations
to the European Commission, European Radio Communications Office, and
European Telecommunications Office.

The GSM Association
The GSM Association (GMSA), founded in 1987, has played a pivotal role in the
development of the GSM platform and of the global wireless industry.
Since its introduction our members and staff have created the landscape
of success for global mobile communications via GSM. Ours is a story of
international cooperation and collaboration, between people, companies
and governments to create the world’s first global wireless network.
The GSMA is the global trade association that exists to promote, protect, and
enhance the interests of GSM mobile operators throughout the world. At the end
of 2004, it consisted of 660 second- and third-generation mobile operators and
more than 150 manufacturers and suppliers. The Association’s members provide
mobile services to nearly 1.3 billion customers across more than 200 countries and
territories around the world. The GSMA aims to accelerate the implementation of
collectively identified, commercially prioritized operator requirements and to provide
leadership in representing the global GSM mobile operator community with
one voice on a wide variety of issues nationally, regionally, and globally.

The European Conference of Postal and
Telecommunications Administration (CEPT)

CEPT, the European Conference of Postal and Telecommunications Administration,
was established in 1959 by 19 countries, which expanded to 26 countries during
its first ten years. Original members were the incumbent, monopoly-holding
postal and telecommunications administrations. CEPT activities included cooperation
on commercial, operational, regulatory, and technical standardization issues.
In 1988, CEPT decided to create the ETSI, European Telecommunications
Standards Institute, into which all its telecommunications standardization activities
were transferred.

In 1992, the postal and telecommunications operators created their own organizations,
Post Europe and ETNO, respectively. In conjunction with the European
policy of separating postal and telecommunications operations from policy-making
and regulatory functions, CEPT thus became a body of policy makers and regulators.
At the same time, central and eastern European countries became eligible for
membership in CEPT. With its 45 members, CEPT now covers almost the entire
geographical area of Europe.

The Telecommunications Industry Association (TIA)
The TIA, Telecommunications Industry Association, is the leading U.S. non-profit
trade association, and represents providers of communications and information
technology products and services for the global marketplace through its core competencies
in standards development, domestic and international advocacy, as well
as market development and trade promotion programs. The association facilitates
the convergence of new communications networks while working for a competitive
and innovative market environment. The TIA strives to further members’ business
opportunities, economic growth and the betterment of humanity through
improved communications.

The American National Standards Institute (ANSI)
ANSI, the American National Standards Institute, is a private, non-profit organization
that administers and coordinates the U.S. voluntary standardization
and conformity assessment system. ANSI’s mission is to enhance both the global
competitiveness of U.S. business and the U.S. quality of life by promoting and
facilitating voluntary consensus standards and conformity assessment systems, and
safeguarding their integrity.

The CDMA Development Group
The CDMA Development Group (CDG), founded in December 1993, is an international
consortium of companies that have joined together to lead the adoption
and evolution of 3G CDMA wireless systems around the world.
The CDG is comprised of CDMA service providers and manufacturers, application
developers and content providers. By working together, the members help
to ensure interoperability among systems, while expediting the availability of 3G
CDMA technology to consumers.

The CDG mission is to lead the rapid evolution and deployment of 3G CDMAbased
systems, based on open standards and encompassing all core architectures, to
meet the needs of markets around the world.

The Association of Radio Industries and Businesses (ARIB)
The ARIB, the Association of Radio Industries and Businesses, was chartered by
the Minister of Posts and Telecommunications as a public service corporation on
May 15, 1995. Its activities include those previously performed by the Research and
Development Centre for Radio Systems (RCR) and the Broadcasting Technology
Association (BTA).

The ARIB was established in response to several trends, such as the growing internationalization
of telecommunications, the convergence of telecommunications and
broadcasting, and the need for promotion of radio-related industries. The ARIB’s
goal is to advance rapidly the use of radio technology for the benefit of society. This is
done by integrating knowledge and experience in various fields of radio use, such as
broadcasting and telecommunications, research and development in radio technology,
and serving as a standards development organization for radio technology.

Telecommunication Technology Committee (TTC)
The TTC, the Telecommunication Technology Committee, contributes to standardization
in the field of telecommunications by establishing protocols and standards
for telecommunications networks and terminal equipment, etc., as well as to
disseminate those standards.

Telecommunications Technology Association (TTA)
The purpose of TTA, the Telecommunications Technology Association, is to contribute
to the advancement of technology and the promotion of information and
telecommunications services and industry, as well as the development of national
economy, by effectively establishing and providing technical standards that reflect
the latest domestic and international technological advances needed for the planning,
design, and operation of global end-to-end telecommunications and related
information services, in close collaboration with companies, organizations, and
groups concerned with information and telecommunications such as network operators,
service providers, equipment manufacturers, academia, R&D institutes, etc.

The Wi-Fi Alliance
The Wi-Fi Alliance is a global, non-profit industry association of more than 200
member companies devoted to promoting the growth of wireless local area networks
(WLANs). With the aim of enhancing the user experience for mobile wireless
devices, Wi-Fi Alliance testing and certification programs ensure the interoperability
of WLAN products based on the IEEE 802.11 specification.

Since the introduction of the Wi-Fi Alliance certification program in March
2000, more than 2000 products have been designated as Wi-Fi CERTIFIED™,
encouraging the expanded use of Wi-Fi products and services across the consumer
and enterprise markets.

Technology Forecasts

2007-07-03T21:53:00.000-07:00

In the different regions around the world, there are different migration or evolution
paths that the technology may take, and these have an impact on the forecasts of technology uptakes. Because GSM is the main global technology, the evolutionary
path through GPRS, and possibly EDGE toward UMTS, sees the greatest
numbers. Other regions starting out from 2G technologies, such as cdmaOne or
TDMA, have a smaller base in the first instance so the forecast figures for these
evolution paths are naturally smaller.

WCDMA in Figure 1.50 represents the deployment of UMTS systems. By the
end of 2004, there were 47 systems in place, with more than 60 more networks
being rolled out in 2005. By contrast, 20 cdma2000 1 x EV-DO had been established.
The adoption of the WCDMA technology is expected to grow at three times
the rate of EV-DO. By the end of 2010, EV-DO will only account for 14 percent
of 3G subscribers.

It is expected that the established 2G networks will linger for some time to
come. Many users in these networks are low-end users, simply making voice calls,
even if they possess a more sophisticated device. This fact will slow the take-up
of 3G subscriptions and therefore the use of 3G services. 2008 will see a stronger
take-up of 3G as people begin to replace their aging 2G handsets, with around
14 percent of the market being 3G. By the end of 2010, 3G will only account for
about 27 percent of the total number of mobile subscribers. The line
marked “Digital” in Figure 1.51 includes GSM, GPRS, EDGE, and cdma2000
1x RTT.

Manufacturers of handsets will continue to produce 2G devices to supply the
demand from developing regions. Many of these will support 2.5G. This explains
the continuing rise in 2G subscriptions. However, a more regional look at the numbers
in Figure 1.52 shows that the developed markets show a decline in 2G subscriptions
in the short term.

ARPU Forecasts
Despite the introduction of 2.5G and 3G networks and services, most operators
are still experiencing a declining average revenue per user (ARPU) figure, particularly
those in the saturated markets. In addition, many 3G operators are coming
to market with aggressively priced voice tariffs, putting further pressure on overall
revenues. It is expected that voice ARPU will continue to decline and data ARPU
will increase by as much as 30 percent when subscribers begin to use the 2.5G and
3G data services offered by the operators

As shown in Figure 1.54, while revenues from data use will increase by up to 83
percent over the next five years, 80 percent of the operators’ revenue will still come
from voice. Falling voice revenues and slowing global growth will contribute to
falling global revenues by 2010.

Prepaid
Prepaid has proved a mixed blessing for operators. It has stimulated rapid growth
in subscriber numbers and driven growth into markets where previously mobile
communications would have been unthinkable. However, it has also been a factor
in driving down ARPU, because prepaid users are often more concerned with cost,
although that is not always the case.

In the recent past, many of the operators in the mature markets have tried to
persuade their prepaid users to move to contracts, regarding this as a way of persuading
them to spend more money. However, this largely proved unsuccessful — many
operators only managed to migrate a fairly minimal percentage to contracts and
then discovered that they did not necessarily spend any more if they did. At the same
time, it was realized that prepaid users are not necessarily low usage or low-spending
users. On the contrary, many prepaid users are from the youth segment, which tends
to contain early adopters for new and lucrative enhanced data services.
As a result, many of the operators have reappraised their strategy for prepaid
and, rather than simply trying to migrate their customers on to contracts, have
used prepaid as a way of accessing certain customer segments that have not been
targeted until now. During 2004, 73 percent of the net additions were for prepaid
(compared with 51 percent in 2003), and the prepaid share of the market rose
to 55 percent. Regional and country markets have shown that as they approach
saturation, the proportion of net additions going to prepaid rises. Therefore, it is
forecast that a steadily increasing share of net additions will go to prepaid over the
forecast period; and by 2009, 64 percent of the total customer base will be using
prepaid.

Global Mobile Markets

2007-07-03T21:48:00.000-07:00

The global market for mobile services is a vast and complicated space. Each country
will have several mobile operators in competition, leading to complex domestic
markets.

Market Overview: China
China’s economy grew 9.5 percent year-on-year in 2004. Telecommunications has
been one of the priority sectors targeted by the Chinese government since the early
1990s in an effort to speed up China’s industrialization process. The telecommunications
sector grew 12.6 percent in 2004 (the mobile market alone grew 18.8
percent), faster than the growth of the overall economy. The industry’s value-added
total accounted for 2.77 percent of China’s GDP in 2004.

The Chinese Mobile Market
China became the world’s largest mobile market in terms of officially counted subscribers
in July 2001. At the end of 2004, there were more than 319 million mobile
users, over 7 million more than fixed-line subscribers (312 million), and 50 million
new mobile customers were added during the year. Of the two operators, market
leader China Mobile enjoys a 64 percent market share but its rival, China Unicom,
has a faster rate of growth, with a compound annual growth rate of 40 percent over
the past three years.

The number of mobile subscribers surpassed that of fixed-line subscribers in
September 2003 (Table 1.8). Mobile capacity had already overtaken fixed capacity
on a national scale the year before, with just six provinces having a greater fixedline
than mobile capacity as of 3Q 2002. Despite the large numbers and robust
growth, however, market penetration stood at 29.6 percent at the end of 2004,
meaning that, unlike most other large mobile markets, there are still many remaining
potential users.

China is a vast country in terms of its population and territory. For historical
reasons, there exists a huge disparity in its economic development across regions.
Large urban centers — Beijing, Shanghai, and Guangzhou — and then, to a lesser
extent, on the eastern seaboard linking these three cities are the forerunners in
economic development; the mobile penetration rate there is significantly more
than 70 percent. However, China’s more remote and rural areas, predominantly
in China’s west, still lack basic access in many places. Therefore, mobile capacity
is considerably lower in the west than in the east and south, with the country’s
industrialized northeast — apart from Beijing, Hebei, and Liaoning — lagging
as well.

China’s mobile sector has been plagued by price wars over the past few years,
despite government pricing rules. As competition stiffens and wireless subscription
rates begin to mature, especially in urban areas and high-end segment, operators
find their revenue growth slackening. In recent years, the new subscribers have
come mainly from the low end. As a result, the overall ARPU has been dropping:
for example, the average ARPU at China Mobile has declined steadily since 2000,
falling from U.S.$19.08 per month in 2001 to U.S.$12.50 by September 2003 and
U.S.$11.10 in 2004.

Operators hope value-added services will help stem the ARPU decline. SMS
has been extremely successful in China over the past years. China Mobile and
China Unicom reported sending 172.57 billion and 44.22 billion SMS, respectively,
in 2004. During the one-week Spring Festival holiday in 2004 alone, 7.8 billion
SMS were sent by China Mobile users and more than 2 billion sent by China
Unicom. Now all the service providers (SPs) derive the majority of their revenues
from SMS.

Other new mobile value-added business grew significantly in 2004. Colour
Ring Back Tone (CRBT), known as another “gold mine” following SMS, won
more than 20 million customers with a market value reaching nearly RMB1
billion (U.S.$121 million) since it was first launched by China Mobile in May
2003. WAP service also maintained a rapid rate of growth, increasing at more than
16 percent per month in the domestic market during the first quarter of 2004,
due to the improvement of 2.5G networks and the active participation of SPs.
By the end of 2004, the number of WAP users grew to 25 million, and the market
value climbed by nearly RMB1.2 billion (U.S.$145 million). In addition,
entertainment services such as mobile games, pictures, and ringtone downloads;
comprehensive information services; and IVR chat services also promised good
prospects.

Chinese Mobile Operators
In July 2004, China Mobile (Hong Kong) Limited successfully completed its
acquisition of the mobile telecommunications companies in ten provinces from its
state-owned parent, China Mobile Communications Corporation, and extended its
network coverage to all provinces in mainland China.

Ranking as China’s largest telecom operator in terms of revenues, China Mobile
posted RMB179.1 billion (U.S.$21.6 billion) in operating revenues in 2003 and
RMB203.9 billion (U.S.$ 24.6 billion) in 2004. It also boasts the world’s largest
mobile subscriber base, with 204.3 million users at the end of 2004, representing
an annual growth rate of 23 percent and commanding 64 percent of China’s
mobile market.

China Unicom (Hong Kong), which owns 30 of China Unicom Telecommunications
Corporation’s 31 provincial networks (the exception being Guizhou),
saw its operating revenue increase by 17.3 percent from 2003 to RMB 79.33 billion
(U.S.$9.59 billion) in 2004. By the end of 2004, China Unicom had a total
of 114.7 million subscribers — 85.9 million GSM subscribers and 28.8 million
CDMA subscribers.

China’s largest fixed-line operator, China Telecommunications Corporation
(China Telecom), was established as a result of the 2002 industry restructuring,
incorporating 21 southern branches of the original China Telecom. Operating revenue
in 2004 was RMB161.2 billion (U.S.$19.5 billion), after acquiring the other
ten provinces from its parent company in April 2004, up 6.4 percent from 151.5
billion (U.S.$18.3 billion) in 2003.

China Telecom offers PAS-based mobile services (known as “Little Smart” in
China. PAS is a personal wireless access system that provides the convenience of a
mobile phone with the cost advantages of a fixed-line phone). Its PAS subscriber base
increased by 67 percent to 43 million at the end of 2004 — from 25.6 million in 2003
— representing 66 percent share of the national PAS market. China Telecom also offers
a CDMA-based limited mobility service, known as “Shihuatong,” in Shenzhen.

China Network Communications Corporation (China Netcom) accomplished
IPO in New York and Hong Kong in November 2004, incorporating six northern
and two southern provinces. It also offers PAS-based mobile services, with 22.5
million PAS subscribers at the end of 2004, more than doubling its customer base
during that year. Total revenues in 2004 reached RMB 64.9 billion (U.S.$7.84 billion),
up 8 percent from RMB 59.9 billion (U.S.$7.2 billion) in 2003.

Like the current China Telecom, China Netcom was established as a result of
the 2002 industry restructuring, incorporating three companies — the original
China Netcom, China Jitong, and 10 northern branches of the original China Telecom
— into the new China Netcom Group. These companies essentially operated
independently until June 2003, when China Netcom purchased China Jitong for
RMB 482 million (U.S.$58.2 million). In 2004, China Netcom Group has split
itself into three companies to operate future businesses in northern China, southern
China, and the global market.

Western Europe
The annual growth rate for the total customer base of western European markets
rose in 2003 (9 percent, versus 7 percent in 2002) and maintained this level in
2004. As a result, 2 million more new customers were added in 2004 than in 2003
and penetration for the region has passed 90 percent (Table 1.10). It is not expected
that this annual growth rate will be maintained now that the penetration is so high.
It is forecast that the growth rate will decline from 2005 onward; despite this, the
regional penetration rate is forecast to exceed 100 percent in 2007.
Nine countries in western European have been profiled and forecast. The total
customer bases of these nine countries accounted for 86 percent of the regional total
at the end of 2004, while their combined populations accounted for 87 percent of
the total. In forecasting for the remaining countries, it is assumed that, because the
markets are very similar, their growth, usage of data, and launch of 2.5G/3G would
be largely the same as the markets that have been forecast.

As expected, commercial 3G services were launched in many of the region’s
markets in 2004 and more than 2 percent of the region’s subscribers (7.3 million)
were using 3G services by the end of the year. This was forecast to rise to 20.9 million
(over 5 percent of the customer base) by the end of 2005. By the end of the
forecast period, we expect there will be 359 million 3G users — 86 percent of the
total mobile users. 2.5G services are also gaining acceptance; in 2004, the number
of 2.5G users doubled to 50.7 million, and by end-2006 there are forecast to be
81.8 million 2.5G subs. By 2007, 3G is forecast to overtake 2.5G, having 95.5 million
subs compared with 2.5G’s 81.9 million subs.

Data services accounted for more than 15 percent of the total revenues in 2004.
This figure is set to increase over the forecast period, and in 2010 nearly 30 percent
of total revenues are forecast to come from non-voice revenues. However, the
increase in enhanced data services does not have the effect of increasing revenues
overall — the ARPU is forecast to drop in western Europe over the forecast period.
This is likely due to competitive data pricing as well as declining voice prices.
Many of the operators have reappraised their strategy for prepaid and, rather
than simply trying to migrate their customers on to contracts, have used prepaid
as a way of accessing certain customer segments that have not been targeted until
now. As a result, there was more focus placed on prepaid; and in 2004, 43 percent
of the total net additions were for prepaid, up from 19 percent in 2003. Even so,
the percentage of total customers who use prepaid offerings fell below 60 percent
for the first time in several years. It is forecast that the percentage of net additions
for prepaid will remain at around 45 percent for the rest of the forecast period, and
prepaid’s share of the total market will decline to 57 percent by end-2010. Overall,
the western European mobile market is forecast to grow by 16 percent over the
forecast period (2004–2010), adding 57.3 million customers.

United States
The U.S. mobile market has been under-penetrated compared with
advanced telecom markets in other regions such as Western Europe and Asia
Pacific. Historically, this was seen as a result of an overly complex and competitive
marketplace — numerous small operators servicing small customer bases — and
a lack of interoperability between the various mobile operators impeding seamless
service offerings. This lack of interoperability was such that roaming agreements
were required while still within the United States.

This complexity has been reduced and U.S. operators have undergone a period
of consolidation, leading to operators with U.S.-wide mobile coverage. During
2004, there was something of an upturn in the market — the annual growth rate
rose and 6.8 million more new customers were added than in 2003 (22.6 million
net additions in 2004 vs. 15.8 million in 2003).

Cingular Wireless’s acquisition of AT&T Wireless, which was completed in
October 2004, has triggered a renewed phase of consolidation in the U.S. wireless
market that has considerably reduced the number of operators. In 1998, 12
operators accounted for 80 percent of the U.S. wireless market. With the merger
of Sprint and Nextel, just four operators account for more than 80 percent of the
market: Cingular Wireless, Verizon Wireless, Sprint Nextel and T-Mobile USA.
More mergers and acquisitions among the smaller players in 2005 — Alltel’s
acquisition of Western Wireless, Alamosa’s acquisition of Airgate PCS, and the
merger of Horizon PCS and iPCS — will consolidate the market even further.
Cingular Wireless’s enlargement has changed the competitive landscape. Cingular
and Verizon had more than half of the total U.S. market at the end of 2004:
Cingular had a 27 percent share (49.1 million subs) and Verizon had a 24 percent
share (43.8 million subs). Even the nationwide operators Sprint PCS and T-Mobile
will find it more difficult to compete, while many of the country’s numerous smaller
regional and local operators are likely to be swallowed up in the long term, unable
to compete independently without enjoying the clear advantages that mergers and
acquisitions bring: economies of scale, OPEX and CAPEX savings, and the advantage
of increased spectrum resources.

Current Mobile Technologies and Markets

2007-07-03T21:45:00.000-07:00

The majority use GSM-based systems, but there are many people who use other
networks’ technologies. This total number of users is expected to grow to 3 billion
users before 2010 as the newer 3G technologies are adopted and the developing
markets begin to take off.

Mobile Generations
Mobile networks are commonly divided into three “generations,” with the third
generation (3G), of which UMTS is one such system, currently being deployed in
networks around the world.

First-generation (1G) systems were analog systems, designed with the simple
aim of making speech services available on the move. They included technologies
such as TACS (Total Access Communication System), NMT (Nordic Mobile Telephone),
and AMPS (Advanced Mobile Phone System). However, even these simple
systems led to annual market growth rates of 30 to 50 percent, leading to around
20 million subscribers by 1990.

However, quality was poor and capability and reliability were low. Thus, as
demand grew, the current range of 2G systems was developed to take their place. The
most well-known of these systems are GSM (Global System for Mobile Communications),
cdmaOne, and the system known in the United States simply as “TDMA,” or
by its standardization label of “IS-136.” These systems were characterized by a move
to representing information digitally and brought the following broad changes:

More consistent and reliable quality of speech

Increased capacity and spectrum efficiency through more advanced modulation
and access schemes

Easier implementation of advanced voice services, text messaging, fax, plus
the addition of basic access to data networks

Enhanced security and fraud prevention

However, even in the move from 1G to 2G (Figure 1.38), the basic aim was still
to optimize for speech services delivered over wide areas (macro cells). 1G and 2G systems
are therefore all characterized by circuit switched networks, which are well suited
to symmetric, real-time “conversational” services. The term “2.5G” is sometimes used
to describe enhancements to second-generation systems that aimed to optimize parts
of these systems for data applications using packet switching techniques.

The latest move, to 3G, further advances digital systems with the particular
aim of increasing the ability to use data applications on the move (i.e., mobile
computing or the wireless office), and to enable “multimedia” services, which may
mix voice, graphics, video, music, etc. To achieve this, a key change is in increasing
the ability of mobile systems to transfer larger quantities of information much
faster.

A factor throughout the evolution of mobile technology has been
the constant improvement in semiconductor and microwave technologies. While
such changes allow for building smaller and more sophisticated mobile equipment,
they also result in the expectation of users for more complex, data-intensive applications
and services.

The GSM Family of Technologies
GSM is a second-generation digital network, supporting voice and simple data services,
including “dial-up” data and text messaging. However, the term “GSM” is also
used to describe the more recent advances in the GSM family: GPRS and EDGE.

The Development of GSM
During the early 1980s, analog cellular telephone systems were experiencing rapid
growth in Europe, particularly in Scandinavia and the United Kingdom, but also
in France and Germany. Each country developed its own system, which was incompatible
with everyone else’s in equipment and operation. This was an undesirable
situation because not only was the mobile equipment limited to operation within
national boundaries, which in a unified Europe were increasingly unimportant, but
there was a very limited market for each type of equipment, so economies of scale,
and the subsequent savings, could not be realized.

The Europeans realized this early on, and in 1982 the Conference of European
Posts and Telegraphs (CEPT) formed a study group called the Groupe Spéciale
Mobile (GSM) to study and develop a pan-European public land mobile system.
The proposed system had to meet certain criteria:

Good subjective speech quality
Low terminal and service cost
Support for international roaming
Ability to support handheld terminals
Support for range of new services and facilities
Spectral efficiency
ISDN compatibility

The developers of GSM chose an unproven (at the time) digital system, as
opposed to the then-standard analog cellular systems such as AMPS in the United
States and TACS in the United Kingdom. They had faith that advancements in
compression algorithms and digital signal processors would allow the fulfillment
of the original criteria and the continual improvement of the system in terms of
quality and cost.

In 1989, GSM responsibility was transferred to the European Telecommunication
Standards Institute (ETSI), and phase I of the GSM specifications was published
in 1990. Commercial service started in mid-1991, and by 1993 there were
36 GSM networks in 22 countries, with 25 additional countries having already
selected or considering GSM. This is not only a European standard; South Africa,
Australia, and many Middle and Far East countries have chosen GSM. By the
beginning of 1994, there were 1.3 million subscribers worldwide. The acronym
GSM now stands for Global System for Mobile telecommunications.

The Mobile Market

2007-07-03T21:43:00.000-07:00

Mobile Market Sectors
The mobile market is a complex place with many different sectors. These will include
the subscriber markets (such as young users and business users) as well as the vendor
markets for hardware and software within the mobile industry. Provision of content
is an area where there is increasing growth and competition.

Operators in the Telecommunications Market
In the arena of telecommunications, there are many types of operators. Some of
these could be considered fixed operators, and some as mobile. There are an increasing
number of operators that appear to offer both fixed and mobile services, through
the use of partnerships and agreements with operators of different kinds of services.
There are also very small regional service providers and very large international carriers
that may have no regional presence.

Fixed Telecom Operators
Small regional operators. There are operators of telecom services that can only
operate in a very specific region. The branding of the company may reflect
this. These companies may own and maintain the wires into domestic and
business premises and the network switching and administration hardware.
Kingston Communications is an example of such a network, offering service
around the North West region of the United Kingdom in Hull.

Incumbent telecom operators. Most countries will have what could be described
as an incumbent telecom operator. Often, these companies are ex-government
run establishments and have represented a market monopoly at some time.
More recently, these state monopolies have been broken up and the markets
have become more liberalized due to regulator intervention.
These networks still exist, however, and continue to offer valuable service
to many individuals and industries within their respective countries,
All the above are the traditional incumbent operators of these countries.
Service providers and billing-only telcos. The regulation and liberalization of
the telecom market have led to a lot of competition in the domestic markets.
The incumbent operators are forced to allow new telecom companies to use
the existing connections to offer services to customers. The public telephone
networks could now be viewed as consisting of the network provider and the
service provider.

The network provider is the company that owns and maintains the wires,
all of or part of the switching infrastructure, and is likely the incumbent
operator. They are obliged to offer the service providers a wholesale rental of
the fixed connection to subscribers’ premises.

The service provider is the company from which the individual or corporate
buys the service; the service provider will not own or maintain the connection
to the subscribers’ premises, but it might operate some switching, billing,
and customer contact systems.

All service providers are accessible to subscribers via the network providers’
connections; this is a condition laid down by the regulator and therefore some
means of connecting the subscriber to the service provider system must be in
place. This might be an indirect access, where the users will dial a prefix before
every call, or there will be a piece of equipment installed at the subscriber’s
home through which calls are made. It is this equipment that will dial the
prefix on behalf of the subscriber.

The alternative is carrier pre-selection (CPS), where the user is automatically
directed to a predetermined network by the network provider. This eliminates
the need for any customer premises equipment or prefixing codes.
Multinational carriers. There are companies that have been around almost
from the beginning of electronic telecommunications. They have grown to
be giants in the industry and offer services over a very wide range of markets,
from domestic phone services to international cable systems and Internet
traffic backbones. These networks (listed in Table 1.1) are often referred
to as Tier 1 carriers. Each of these companies will have a presence in more
than one country and some own sub-sea telecom cables or satellite systems.
Companies such as Verizon, AT&T, and Cable & Wireless have a very large
portfolio of international voice and data services.

Mobile Telecom Operators
Mobile network operators (MNOs). An operator of a mobile network is a company
or organization that has obtained a license to operate and has invested in
all the necessary equipment to provide radio coverage and telephony services
for members of the general public. Mobile network operators own, operate,
and maintain all the telecom equipment themselves or make use of contractor
services for some of this work.

In the interest of competition, there will usually be more than one operator
in a country; this would be a condition set by the government or regulator
of the region.

Mobile virtual network operators (MVNOs). It is increasingly common for
organizations to offer mobile phone service to the general public where the
organization does not own or operate a mobile infrastructure. These entities
are called mobile virtual network operators (MVNOs). An MVNO is an organization
that has made an agreement with one of the existing “real” mobile
operators to carry services and products on their behalf. An MVNO will
brand the product, services, and handsets as if it were they themselves that
were operating a network. This may be a cost-effective way for supermarket
chains, music stores, and youth-related industries to move into the mobile
service arena. A real operator can also make use of MVNO branding to target
niche segments of the market such as youth culture, gaming, etc.
There are several definitions of an MVNO, and Table 1.3 shows some of
the areas where differences exist between normal operators, MVNOs, and
other providers of mobile service.

Currently, there are approximately 200 planned or operational MVNOs
worldwide. Countries such as the Netherlands, Denmark, United Kingdom,
Finland, Belgium, and the United States have the most MVNOs per country,
whereas some are just beginning to launch active MVNO business models
(e.g., France, the Baltics, and Austria).

Presently, many companies and regulatory bodies are strongly in favor of
MVNOs. For example, in 2003, the European Commission issued a recommendation
to national telecom regulators (National Regulatory Authority
[NRA]) to examine the competitiveness of the market for wholesale access
and call origination on public mobile telephone networks. The study resulted
in new legislation from NRA in countries such as Ireland and France that
forces operators to open up their network to MVNOs. Appendix A lists some
of the MVNOs and MVNO activity from three countries.

Mobile virtual network enabler (MVNE) (Figure 1.26). An MVNE provides
infrastructure and services to enable MVNOs to offer services and have a
relationship with end-user customers but does not have a relationship with
those end-user customers.

An MVNE offers infrastructure and related services, ranging from network
element provisioning, administration, and operations to operational
support system/business support systems (OSS/BSS) support. MVNEs often
provide the “middle ground” between MVNOs that do not want to have any
control over network elements and those that want complete control.

Mobile Network Services

2007-07-03T21:41:00.000-07:00

Many of the services offered by the mobile networks are the same or similar to those
of the fixed networks. The original service was voice. The technology in the early
days of mobile networks was not capable of much more than just voice. Technology
both in the networks and in the handsets, has advanced massively over the past 20
years, leading to more complex and sophisticated services. Operators are focusing
particularly on data and data services, hoping that it will be a way to sustain growth
and revenue in the networks. However, with the complexity of these services and
the handsets used to access the service, many subscribers are simply not using them.
A major challenge for the near future is for the networks to create services that the
population of subscribers actually want and for the handset manufacturers to find
a way of presenting the service in a simple and easy to use way.

Basic services. Because a mobile phone network is principally a voice telephony
network, it seems reasonable that some of the services seen in the fixed network
transfer to the mobile systems.

Short Message Service (SMS). SMS is a text-based message service that allows
subscribers to exchange messages of up to 160 alphanumeric characters. This
service was developed as part of the GSM system and has become a very
popular service during the past few years. Recent statistics show that some
networks are handling more than a billion text messages per month. SMS has
evolved from a simple text messaging service to one that allows the transport
of other forms of media, including ringtones, pictures, operator logos, wallpapers,
and screensavers for mobile devices. Many of the services mentioned
here, however, are proprietary to a particular make and model of mobile
phone. There are similar services available today that use different methods
for transporting the media, which tends to be more compatible over the range
of mobile makes and models.

The text messaging service is also finding new applications. SMS short
codes, normally five digits, can be used to interact with TV shows and radio
stations, subscribe to information services, and to make payments for goods
or services.

Mobile data services. Since the advent of digital mobile radio, it has been possible
— at least in theory — to send and receive data from mobile phones.
It has, however, taken many years for data services to become popular. The
problem is that, apart from corporate users, general members of the public
are not interested in buying or subscribing to a “data service” such as dial-up
connections at 9.6 kbps or even more efficient and faster GPRS connections
at up to 40 kbps.

What subscribers want is a useful and engaging service accessible through
a simple and reliable interface. The job, then, of mobile network service providers,
content providers, and mobile manufacturers is to find such a service
and make it available at a price that is appealing. A simple enough statement
to make here, but very difficult to execute effectively, given also that in the
past, subscribers have had bad experiences with data services.

Services that make use of a data connection. Once the mobile equipment and
the network are capable of transferring data at a rate considered reasonable, it
is possible to build applications that will exchange information in such a way
to offer the user a service that he or she may find useful.

Data transfer services. Business users have a different requirement from normal
subscribers. They normally require access to e-mail services, file transfers, and
databases. All these types of services are normally run on portable computing
equipment such as laptops and PDAs (personal digital assistants). This equipment
is often connected to the network using the mobile phone as if it were a
modem; in this way, the applications on the laptop are able to exchange information
through the data pipe provided by the connection

Services and the User Perspective

2007-07-03T21:39:00.000-07:00

Access to Network Services

The Changing Nature of Services

Relatively unsophisticated technology and networks meant that customers have
historically been presented with a fairly narrow range of services from which to
choose. The most common service is still that of voice telephony, but over the
past few years (especially the past 20), customers have been given the option of an
increasing number of valuable and sometimes novel services.

Network operators are keen to provide these services in an effort to increase
revenue. This is made more important as the margins for voice calls decrease. An
additional fact is that networks need to keep existing customers and attract new
ones. Different and desirable services are a proven method of achieving this.
With the advent of the Internet and all that it brings in terms of information,
together with increasing mobility in the form of cellular networks such as GSM,
there is a thirst for new and relevant services. With the most innovation-receptive
customers often opting for mobile phones, and the average age of mobile phone
users decreasing dramatically over the past few years, the uptake of new services,
features, gadgets, and applications is all but assured. New, flexible ways of providing
services are now being implemented. The shackles are coming off service creation.
The nature of services and their implementation is changing rapidly.

Increasing Service Needs
Users had relatively simple needs in the early days of telecommunications, mainly
because they had little knowledge of what was possible as the next step. Simple
voice calls completely dominated telecommunications for at least half a century
and provided the majority of traffic on a network for a full century.

Faster call setup, worldwide coverage, and more affordable services were largely
achieved as a result of advances in technology and organization. Data services, however,
were provided partly as an advance in technology, but developed in response
to customer needs.

As the age of mobility and advanced service offerings approached, the pull of
the customers’ needs became much more of a factor. At the present time, customers’
needs are top priority, evidenced occasionally by media hype about a new service
that fails to deliver on its promise (at least initially) due to technology constraints.
The near future looks bright in terms of services, with customer demand on the
way to being met by flexible systems with greater bandwidth, more control data,
and more innovation than ever before.

Telecommunications Services

Defining a Telecommunications Service

A service offered by a telecommunications company is a product that enables two
or more people to exchange information over a long or short distance. The nature
and complexity of the service is often reflected in the price the customer has to pay.
It was not too long ago that the choice of service was very limited. This was due, in
part, to there being little competition in the market, and also to the level of technology
deployed. Today, however, in the deregulated and liberalized telecom market,
there are many companies competing in the same commercial space, which leads to
innovation and development as companies strive to be different. The consumer looking
for service in the fixed or mobile arenas is faced with a multitude of apparently
different products from many different service providers or telecom companies.

Services in the Fixed Network
Fixed networks traditionally provide wired services, such as direct dial voice.
Increasingly, the networks are offering many more advanced services that include
data connections.

Voice. Voice is the most basic service offered, and the one the customer is most
likely to expect. This is the service that is taken for granted when considering
telecommunication networks and, for the operators of the networks, speech
is still by far the largest revenue generator.

Emergency call. The once ubiquitous telephone box in the street is to allow
all citizens access to the emergency call service. Regulators insist that the
emergency services operator is available to every customer of a telecom network
and that the service is free of charge. The reason many networks still
maintain the telephone box in the street is to allow all citizens access to the
emergency call service.

Defining Areas of the Network

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In both fixed and mobile networks, it is possible to divide the network into various
parts according to their function, some parts of the
network deal with connection to the user and others handle the management of the
users and the services they wish to consume.

The Access Network
In the fixed network, the access network consists of the wires and
cable that allow users to be connected to the central part of the network where
access to services can be obtained. This is often the largest and most complicated
part because it relies on a pair of copper wires or cable being delivered to every subscriber
in the network. In a very large network, this can mean that tens of millions
of wires must be connected from the users’ premises and run back toward the core
network. To reduce the overall complexity, the access network will often contain
devices that will allow the information from many wired connections to be sent on
a single cable. This reduces the total number of wires in the system.
In some parts of the world, the copper infrastructure is in very poor condition
due to lack of maintenance or local conditions. Some operators choose to establish
wireless local loop (WLL) style systems, which eliminate traditional copper wires.
WLL systems should not be confused with mobile radio systems because they form
part of the connection to a user’s fixed device.

The access network is able to carry voice information (most likely in analog format)
and data where the condition of the line allows. It is becoming more common
for domestic premises to have both a speech and a broadband connection with the
network service provider.

The Radio Access Network
The difference between radio system and fixed system is that the user’s terminal
is a mobile device. The user then has the freedom to move anywhere within the
system radio coverage area and expect to communicate with the core network.
Radio access networks (Figure 1.15) are most often associated with cellular phones
systems, but PMR and other radio systems such as pagers can be considered mobile
radio systems.

The purpose of the radio access network is to allow the users to make connections
to the core network anywhere in the coverage area of the network. It is able to
do this by placing radio base stations around the area where service is required. The
mobile device then uses radio signals to relay the user’s information or voice to the
core network via the base station.
Satellites can also be part of a radio access network. The satellites are simply
radio base stations that orbit the Earth instead of being fixed on the ground.

Core Networks
If the radio access network is there to provide connection to the core network, then
the core network exists to provide the service to the user.
The core network (Figure 1.16) is a complex system of switches, interfaces,
databases, and transmission systems, all designed to offer the users of the network
telephone call, a relatively simple service for the user, but one that still requires a
great deal of complexity in the networks.

Today’s modern systems often separate the core of the network
into two distinct areas: (1) voice service and (2) data services. The core network
concerned with voice primarily deals with the routing of telephone calls and those
services normally associated with telephony, such as call waiting, call hold, etc.
Connections to external telephone systems such as the other public telephone systems
or between mobile networks or the international networks are also made from
the voice-based core network. The data side of the network deals with data connections
and the routing of data to connected data terminals. External connections are
also supported, most probably to the public Internet or to local networks associated
with business systems.

Other Types of Networks
There are some other types of networks that perhaps do not fit into the precise
definitions given above. These are networks that perhaps do not have an access
network and do not offer their services directly to members of the public. Their customer
is more likely a large business or the fixed and mobile operators themselves.
These networks provide long-distance connections within countries or connections
between countries. They are the national and international carriers.
It is often the case that a large incumbent fixed operator will offer its service to
domestic subscribers via an access network and also provide long-distance connections
via its core networks for enterprises requiring fixed point-to-point connections.
These types of connections are often referred to as leased lines.
Some of these very large (Tier 1) networks will also own or connect to the international
networks to allow calls to be routed between countries around the world.

Mobile Communication Networks

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Mobile networks differ from fixed networks in that the “last mile” (or the connection
to the user) is based on radio transmission techniques. This wireless service
gives the user the added benefit of mobility in the local area or wider area, depending
on the nature of the network.

Background to Mobile Radio
Wireless communication, either as part of a fixed network to extend the communications
without the need to install physical wires or as the connection to the user,
has been a goal ever since the advent of long-distance communications. Providing
a wireless connection to the user involves overcoming a large number of problems,
not the least of which is the size of the radio equipment that the user would be
expected to carry around.

Mobile radio systems have been around almost since the development of radio
technologies. One of the first installed mobile radio services was in the 1920s by the
police in Detroit. Mobile, in this case, meant that the radio equipment was small
enough to carry around in a vehicle. Early systems like this tended to be one-way
radio. It was not until the technology was pushed forward by World Wars I and II
that two-way radio began to emerge. Then the development of commercial radio
systems began.

Private Mobile Radio (PMR)
Mobile radio service used to be the preserve of military and commercial organizations.
The nature of the service was also very different from the telephone-style
service we expect today. However, an important element of modern radio systems
reflects the older style of service. Today we refer to these systems as Private or Public
Access Mobile Radio (PMR/PAMR).

Typical uses include emergency services, courier/delivery, and utilities and
dispatching services. The nature of this communication is point-to-multipoint or
group working (Figure 1.10). Interestingly, the public cellular operators are beginning
to offer similar services as value-added services on their networks.

Cellular Radio
Advances in technology and radio spectrum management have led to the development
of “cellular” radio networks, allowing the networks to support many users
over a wide area. Cellular refers only to the method of using the radio spectrum
available (Figure 1.11). Many different radio technologies can use cellular deployment
of radio channels. However, we often use the term “cellular” to mean a mobile
phone network such as GSM or cdmaOne.

Analog Mobile Networks
The first mobile phone networks began to appear in the latter part of the 1970s.
These systems were analog and supported a very limited service. Analog networks
do not naturally support data transmission. Modems could be purchased to allow
users to move data or send faxes, but this was expensive and slow. The handsets
were often bulky and had poor battery life (Figure 1.12). However, during the
1980s, many advances in all aspects of mobile phone technology meant that handsets
became smaller and more reliable, and battery life also improved.

Types of Networks

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Introduction to Telecommunications Networks
In the world of telecommunications (telecom), there are many ways and means of
exchanging information, and the nature of that information can be just as varied. As
a result, there are many different kinds of telecommunications networks: fixed and
mobile, data and voice, analog and digital. Today, networks such as the Internet allow
the transfer of many different types of data, regardless of the underlying technology.
Fixed Communication Networks
The term “fixed” usually refers to the last mile in the communication link. This
fixed part connects the user’s equipment to the telecom network using some type
of physical medium. Copper wires are the most common form of connection but
they may also include coaxial cable or, less commonly, fiber optics. In some cases
it is possible to provide a fixed connection using a radio connection. These types of
systems are often referred to as wireless local loop (WLL)

Public Switched Telephony Network (PSTN)
The PSTN (Figure 1.6) is the publicly available dial-up telephone network. It is a
complex interconnection of switching centers and end users that offers a voice connection
between any two valid subscribers. In addition, international connections
to other countries are also possible. In engineering parlance, the PSTN is sometimes
referred to as POTS, an acronym for plain old telephone system.

Connections to the PSTN
As telephone communications evolved, telephone exchanges were used to manually
connect users together. A pair of wires ran (typically overhead) from each subscriber
to the exchange where these were terminated at a switchboard. An operator then
interconnected subscribers in a manual process using short cables. As the number
of subscribers increased, the demand for physical space to house the switchboards
and operators also increased. This led to massive exchange buildings and armies of
staff required to operate the system.
The development of automatic exchanges (or switches) using electromechanical
devices simplified the interconnection of subscribers and reduced the amount of
space and manpower required. This was taken a stage further by the implementation
of digital switches. The only part of the network that remains in its original
form is the pair of wires that forms the final connection to the subscriber, commonly
known as the local loop.

Analog to Digital
Speech by its very nature is an analog signal, and early systems such as the manual
network mentioned above merely carried the signal from end to end. In modern
networks, this signal is digitized to preserve audio quality and then carried across
the network using digital links and switches (Figure 1.7).
Integrated Services Digital Networks (ISDN)
The modern digital telephony network not only carries voice, but also data at 64
kbps. This service is called an integrated digital network (IDN). As discussed above,
there remains a short local loop of analog service over a pair of wires. The next stage
is to take the digital channels all the way to the customer so that all services can be
integrated on one bearer. This is the Integrated Services Digital Network (ISDN).
The ITU-T defines ISDN as:
A network evolved from the telephony IDN that provides end-to-end
digital connectivity to support a wide range of services, including voice
and non-voice services, to which users have access by a limited set of
standard multipurpose customer interfaces.

The Mobile Telecommunications Market

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The Telecommunications World
At the beginning of the new millennium, telecommunications, in its various forms,
is revolutionizing both our society and the world economy. This book shows how
technologies have developed, how they work, how they are being utilized today, and
how they are likely to come together to satisfy the needs of consumers in the future.
The term “telecommunications,” as shown in Figure 1.1, incorporates the following
areas:
Voice communications
Data communications
Radio systems
Navigational systems
Mobile networks
Fixed networks
Broadcast networks
We explore each of these areas to see how both technology push and market pull have
acted upon them to create the telecommunications environment we have today.
The next few years will see big changes in the telecommunications industry. If all
goes according to plan, the consumer will feel the benefits of greater choice; advanced,
user-friendly, and more personal services; new billing models; enhanced customer
care; and a greater focus on content rather than the underlying technology.
The Evolution of Telecommunications
From Homer to Marconi
Homer, speaking of the fall of Troy in the 11th Century BC, described a chain of
beacons that were used to send the news back to Argos. This is one of the earliest
examples of communication over a significant distance. (Figure 1.2.) The setting
of the story in Greece is significant because the word “telecommunication” derives
from the Greek word tele, meaning far or distant. As we will see, today the term
“telecommunication”
is applied to both short- and long-distance communication
by electronic means.

The first invention that sought to bring about long-distance communication
was the telegraph. The first models utilized 26 pairs of wires, one to transmit each
letter of the alphabet. Samuel Morse saw the need to reduce the number of wires
to one, which he achieved in 1838. To make his telegraph machine function on a
single connection, he devised a coding system that produced an ECG-like line on
tickertape. It was only later that one of his assistants produced the now-familiar
dots and dashes version of the code that could be sound read by the operators. By
1854 there were 23,000 miles of telegraph cable in use, with the first trans-Atlantic
cable link established in 1868.

When Alexander Graham Bell invented the telephone in 1876, not everyone
was impressed. The Engineer-in-Chief of the British Post Office commented, “My
department is in possession of full knowledge of the details of the invention, and
possible use of the telephone is limited.”

The early telephony systems employed operators who would manually connect
one customer’s line to another. On discovering that the local operator was diverting
calls to a business rival, a St. Louis undertaker, Amon Strowger, invented dial
telephony. As with so many developments within the field of telecommunications,
necessity proved to be the mother of invention.

At the end of the 19th Century, Marconi’s invention of the radio telegraph
was key to the development of future radio-based technologies. Using existing discoveries
and inventions, he was able to build a working system that could initially
transmit up to a distance of 2.4 kilometers. By 1899 he had refined his system so
that British battleships could transmit up to a distance of 121 kilometers.

From Marconi to Telstar
At the turn of the century, Marconi sent the first radio signal across the Atlantic,
despite the predictions of his contemporaries that this would fail due to the curvature
of the Earth. They had failed to appreciate that the Earth’s atmosphere could
be used to reflect radio waves.

Television made an appearance in 1926, when Baird produced his electromechanical
machine. As is so often the case, a rival system proved to be just around
the corner. Farnsworth demonstrated the superior electronic television in 1927
that, thankfully, became the forerunner of today’s televisions.
As shown in Figure 1.3, over the next few decades a number of new technologies
were developed that proved essential for the development of our modern telecommunications
systems. In 1947, the transistor was invented, offering great reductions
in the size of telecommunications equipment. The launch of the first communications
satellite in 1962 and the development of fiber-optic cable four years later accelerated
the pace of development for high bandwidth telecommunications.

The Internet and Mobile Communications
The 1970s saw the beginnings of the Internet with the introduction of ARPANET.
The original system was designed to encompass many networks from universities
and government institutions. However, it took the development of the TCP/IP
protocol in 1974 and the subsequent design of the World Wide Web in 1989 by
Tim Berners-Lee to make the Internet as easily accessible as it is today.

Telecommunications Today
The world of telecommunications today is a vast and complex place, encompassing
mobile, fixed, and Internet connections. In past times, telecommunications
and data communications were seen and treated as completely separate fields of
technology. It is not possible today to talk of one and neglect the other; voice and
data communications have converged in both mobile and fixed networks. The next
significant development, already underway, is the convergence of mobile and fixed
networks, providing subscribers with unified communications systems that allow
consumers a huge choice in the mode of their communication with another user
or service.

ACRONYMS

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1xEV-DO 1x Evolution-Data Optimized
21CN 21st Century Network
3GPP 3rd Generation Partnership Project
3GPP2 3rd Generation Partnership Project 2
A2DP Advanced Audio Distribution Profile
AAC Advanced Audio Codec
ACELP Algebraic Code Excited Linear Prediction
ADSL Asymmetric Digital Subscriber Line
ARFCN Absolute Radio Frequency Channel Number
AM Amplitute Modulation
AMPS Advanced Mobile Phone System
AMR Adaptive Multi-Rate codec
ANSI American National Standards Institute
API Application Programming Interface
ARIB Association of Radio Industries and Businesses
ARPU Average Revenue Per Unit or Average Revenue Per User
ASK Amplitute shift keying
ATM Asynchronous Transfer Mode
ATRAC Adaptive TRansform Acoustic Coding
AuC Authentication Center
BER Bit Error Rate
BES BlackBerry Enterprise Server
BMP Bitmap
BREW Binary Runtime Environment for Wireless
BSS 1) Business Support System; 2) Base Station Subsystem
BT British Telecom
BTS Base Transceiver Stations
C/I Ratio Carrier-to-Interference Ratio
c-HTML Compact HTML
CAMEL Customized Applications for Mobile network Enhanced Logic
CAP CAMEL Application Part
CC Call Control
CCD Charge-Coupled Device
CCSA China Communication Standards Association of China
CDC Connected Device Configuration (J2ME)
CDG CDMA Development Group
CDMA Code Division Multiple Access
CDMA2000 1x RTT Code-Division Multiple Access (CDMA) 1x
(single-carrier) Radio Transmission Technology
CEIR Central Equipment Identity Register
CEPT European Conference of Postal and Telecommunications
(Conférence européenne des administrations des postes
et des télécommunications)
CIF Common Interchange Format
CLDC Connected Limited Device Configuration (J2ME)
CMOS Complementary Metal-Oxide Semiconductor
CS Coding Scheme
CSCF Call Session Control Function
CTP Cordless Telephony Profile (Bluetooth)
CVSD Continuously Variable Slope Delta-modulation
D-AMPS Digital Advanced Mobile Phone System
dB decibels
DBS Direct Broadcast Satellite
DCE Data Circuit-terminating Equipment
DECT Digital Enhanced (formerly European) Cordless
Telecommunications
DMB Digital Multimedia Broadcasting
DNP Dial-up Networking Profile (Bluetooth)
DRAM Dynamic Random Access Memory
DRM Digital Rights Management
DSL Digital Subscriber Line
DSLAM DSL Access Multiplexer
DSP Digital Signal Processing
DTE Data Terminal Equipment
DTMF Dual-Tone Multi-Frequency
DTT or DTTV Digital Terrestrial Television
DVB Digital Video Broadcast
DVB-H Digital Video Broadcasting-Handheld
DVB-T Digital Video Broadcasting-Terrestrial
DVD Digital Versatile Disc (formerly Digital Video Disc)
DWDM Dense Wavelength Division Multiplexing
E-OTD Enhanced Observed Time Difference (UMTA)
E2PROM Electronically Erasable Programmable Read-Only Memory
EDGE Enhanced Data rate for GSM Evolution
EEPROM Electronically Erasable Programmable Read-Only Memory
EFR Enhanced Full-Rate codec
EHF Extra High Frequencies
EHR Enhanced Half-Rate codec
EIR Equipment Identity Register
EMC ElectroMagnetic Compatibility
EMS Enhanced Messaging Service
ERTMS The European Railway Traffic Management System
ESN Electric Security Number
ETNO European Telecommunications Network Operators’ Association
ETSI European Telecommunication Standards Institute
EvDO Evolution Data Optimized
EVDV Evolution Data Voice
FDD Frequency Division Duplex
FDM Frequency Division Multiplexing
FDMA Frequency Division Multiple Access
FM Frequency Modulation
FR 1) Frame Relay; 2) Full Rate codec
FSK Frequency Shift Keying
GAP Generic Access Profile (Bluetooth)
GCF Global Certification Forum
GGSN Gateway GPRS Support Node
GIF Graphics Interchange Format
GMSC Gateway Mobile Switching Center
GMSK Gaussian Minimum Shift Keying
GPRS General Packet Radio Services
GPS Global Positioning System
GRX GPRS Roaming eXchange
GSM Global System for Mobile Communications
GSMA The GSM Association
GSN GPRS Support Node
HSCSD High-Speed Circuit Switched Data
HDSL High-speed Digital Subscriber Line
HF High Frequency
HLR Home Location Register
HR Half-Rate codec
HSDPA High Speed Downlink Packet Access
IETF Internet Engineering Task Force
IMEI International Mobile Equipment Identity
IMS IP Multimedia Subsystem
IMT-2000 International Mobile Telecommunications-2000
IN Intelligent Network
INAP Intelligent Network Application Part
IP 1) Internet Protocol: 2) Intercom Profile (Bluetooth)
ISDN Integrated Services Digital Network
IOT InterOperability Testing
IrCOMM Provides COM (serial or parallel) port emulation or connections
using IrDA protocol
IrDA Infrared Data Association
IrMC Infrared Mobile Communications
ISI Intersymbol Interference
ISO International Standards Organization
ITU International Telecommunication Union
ITU-R ITU Radiocommunication Sector
ITU-T ITU Telecommunication Standardization Sector
IWF InterWorking Function
J2ME Java 2 Micro Edition
JPEG Joint Photographic Experts Group
KVM K Virtual Machine (J2ME)
LA Location Area
LAC Location Area Code
LCD Liquid Crystal Display
LIF Location Interoperability Forum
LR Location Register
MGIF Mobile Gaming Interoperability Forum
MHz Megahertz
MIDI Musical Instrument Digital Interface
MIDP Mobile Information Device Profile (J2ME)
MIMO Multiple-Input Multiple-Output
MIPS Million Instructions Per Second
MM Mobility Management
MMCA MultiMediaCard Association
MMS Multimedia Messaging Service
MMSE Multimedia Messaging Service Environment
MNO Mobile Network Operator
MPEG Motiving Pictures Expert Group
MPLS Multi Protocol Label Switching
MSAN MultiService Access Node
MSISDN Mobile Station International ISDN Number
MSC Mobile Switching Center
MSS Marketing Support System
MTP Many-Time Programmable memory
MVNE Mobile Virtual Network Enabler
MVNO Mobile Virtual Network Operator
MWIF Mobile Wireless Internet Forum
nm nanometer
NMT Nordic Mobile Telephone
NNG National Number Group
NTS Number Translation Services
OEM Original Equipment Manufacturer
OLED Organic Light Emitting Device
OMA Open Mobile Alliance
OPP Object Push Profile (Bluetooth)
OSA Open System Architecture
OSS Operational Support System
OTDOA Observed Time Difference of Arrival (GSM)
OTP One-Time-Programmable memory
P-TMSI Packet-Temporary Mobile Subscriber Identity
P2T Push-to-Talk
PAMR Public Access Mobile Radio
PCM Pulse Code Modulation
PCMCIA 1) Peripheral Component MicroChannel Interconnect
Architecture; 2) Personal Computer Memory Card International
Association
PCU Packet Control Unit
PDA Personal Digital Assistants
PDC Public Digital Cellular
PDP Packet Data Protocol
PDH Plesiochronous Digital Hierarchy
PDN Packet Data Network
PIM Personal Information Management
PLMN Public Land Mobile Network
PM Phase Modulation
PMR Professional Mobile Radio (Private Mobile Radio in the UK)
PNG Protable Network Graphics
PoC Push to talk over Cellular
POTS Plain Old Telephone Service
PROM Programmable Read-Only Memory
PSE Packet-Switching Exchange
PSK Phase Shift Keying
PSS 1) Packet Switched Stream; 2) Packet-switched Streaming Service
PSTN Public Switched Telephone Network
PTT 1) Postal, Telegraph and Telephone; 2) Push To Talk
QCIF Quarter Common Interchange Format
QoS Quality of Service
R&TTE Radio and Telecommunications Terminal Equipment directive
RA Routing Area
RAM Random Access Memory
RAN Radio Access Network
ROM Read-Only Memory
RNC Radio Network Controller
RR Radio Resources
RSN Robust Security Network (802.11i)
RTT Radio Transmission Technologies
SBC SubBand Coding
SCP 1) Service Control Point; 2) Service Control Platform
SDAP Service Discovery Application Profile (Bluetooth)
SDH Synchronous Digital Hierarchy
SHF Super High Frequency
SGSN Serving GPRS Support Node
SIM Subscriber Identity Module
SIP Session Initiation Protocol
SIR 1) Signal to Interference Ratio; 2) Serial InfraRed
SM Session Management
SME Small and Medium Enterprise
SMS Short Message Service
SMSC Short Message Service Center
SNR Signal-to-Noise Ratio
SOAP Simple Object Access Protocol
SONET Synchronous Optical NETwork
SPP Serial Port Profile (Bluetooth)
SRAM Static Random Access Memory
SS7 Signaling System #7
SSP Service Switching Point
STM Synchronous Transport Mode
STN Super-Twisted Nematic display
TACS Total Access Communications System
TCP/IP Transmission Control Protocol/Internet Protocol
TD-SCDMA Time Division Synchronous CDMA
TDD Time Division Duplex
TDM Time Division Multiplexing
TDMA Time Division Multiple Access
TETRA TErestrial Trunked RAdio
TFT Thin Film Transistor
TIA Telecommunications Industry Association
TMSI Temporary Mobile Subscriber Identity
TN Twisted Nematic display
UHF Ultra High Frequency
UICC Universal Integrated Circuit Card
UM Unified Messaging
UMTS Universal Mobile Telecommunications System
URI Uniform Resource Identifier
USB Universal Serial Bus
USIM Universal Subscriber Identity Module
UTRA Universal Terrestrial Radio Access
UTRAN UMTS Terrestrial Radio Access Network
UWC-136 Universal Wireless Communications-136
VAS Value Added Service
VASP Value Added Service Provider
VDSL Very high-speed Digital Subscriber Line
VGA Video Graphics Array
VHE Virtual Home Environment
VLF Very Low Frequencies
VM Virtual Machine
VLR Visitor Location Register
VoIP Voice over Internet Protocol
VPN Virtual Private Network
VLR Visitor Location Register
W3C The World Wide Web Consortium
WAN Wide Area Network
WAP Wireless Application Protocol
WCDMA Wideband Code Division Multiple Access
WDM Wave Division Multiplexing
WiMAX Worldwide Interoperability for Microwave Access
WLAN Wireless Local Area Network
WLL Wireless Local Loop
WML Wireless Markup Language
WPA Wi-Fi Protected Access
WRC World Radio Conference
WSDL Web Service Definition Language
WWAN Wireless WAN
X.25 ITU protocol standard for WAN communications
XMF eXtensible Music Format
XML Extensible Markup Language