More coursework: 1 - A | B | C | D | E | F | G | H | I - J | K - L | M | N - O | P - S | T | U - Y

Integration of umts and bisdn is it possible or desirable



In the future, existing fixed networks will be complemented by

mobile networks with similar numbers of users. These mobile

users will have identical requirements and expectations to the

fixed users, for on-demand applications of telecommunications

requiring high bit-rate channels. It will be necessary for

these fixed and mobile networks to interoperate in order to

pass data, in real time and at high speeds, between their


But how far must this interoperation be taken? How much

integration of the fixed and mobile network structures is

needed? Here, a fixed network, B-ISDN, and a mobile network,

UMTS, under development at the same time, are examined to see

how well and closely they should work together in order to

meet expected user needs. Work already taking place on this is



The Universal Mobile Telecommunication System (UMTS), the third

generation of mobile networks, is presently being specified as

part of the European RACE technology initiative. The aim of

UMTS is to implement terminal mobility and personal mobility

within its systems, providing a single world mobile standard.

Outside Europe, UMTS is now known as International Mobile

Telecommunications 2000 (IMT2000), which replaces its previous

name of Future Public Land Mobile Telecommunication System


UMTS is envisaged as providing the infrastructure needed to

support a wide range of multimedia digital services, or

teleservices [CHEU94], requiring channel bit-rates of less

than the UMTS upper ceiling of 2 Mbits/second, as allocated to

it in the World Administrative Radio Conference (WARC) '92

bands. UMTS must also support the traditional mobile services

presently offered by separate networks, including cordless,

cellular, paging, wireless local loop, and satellite services.

[BUIT95] Mobile teleservices requiring higher bit rates, from

2 to 155 Mbits/second, are expected to be catered for by

Mobile Broadband Services (MBS), the eventual successor to

UMTS, which is still under study. [RACED732]

Broadband Integrated Services Digital Network (B-ISDN),

conceived as an all-purpose digital network that will

supersede Narrowband ISDN (N-ISDN or ISDN), is also still

being specified. B-ISDN, with its transport layer of

Asynchronous Transfer Mode (ATM) is expected to be the

backbone of future fixed digital networks. [MINZ89]

It is anticipated that, by the year 2005, up to 50% of all

communication terminals will be mobile. [CHEU94] The Mobile

Green Paper, issued by the European Commission in 1994,

predicts 40 million mobile users in the European Union by

2000, rising to 80 million by 2010. This gives mobile users an

importance ranking alongside fixed-network users. [BUIT95]

One result of this growth in mobile telecommunications will be

the increase in teleservice operations that originate in

either the fixed or mobile network, but terminate in the

other, crossing the boundary between the two. UMTS is expected

to be introduced within the next ten years, and integration

with narrowband and broadband ISDN is possible in this time.

Interoperability between UMTS and ISDN in some fashion will be

necessary to support the interoperability between the fixed

and mobile networks that users have already come to expect

with existing mobile networks, and to meet the expectation of

consistency of fixed/mobile service provision laid out in the

initial RACE vision. [SWAI94]

One way of making UMTS attractive to potential customers is to

offer the same range of services that B-ISDN will offer,

within the bounds of the lower 2 Mbits/second ceiling of UMTS.


So, with the twin goals of meeting existing expectations and

making UMTS as flexible as possible to attract customers, how

closely integrated must UMTS be with B-ISDN to achieve this?


The UMTS network could be developed along one of the following

alternative integration paths:

1. Developing an 'optimised' network structure and signalling

protocols tailored for the special mobile requirements of

UMTS. This would be incompatible with anything else. Services

from all fixed networks would be passed through via gateways.

This design-from-scratch method would result in highly

efficient intra-network operation, at the expense of highly

inefficient inter-network operation, high development cost,

scepticism relating to non-standard technology, and slow

market take-up. True integration with fixed networks is not

possible in this scenario.

Given the drawbacks, this is not a realistic option, and it

has not been considered in depth. One of the RACE goals was to

design UMTS not as a separate overlay network, but to allow

integration with a fixed network; this option is undesirable.


2. Integration with and evolution from the existing Global

System for Mobile telecommunication. (GSM, formerly standing

for Group Special Mobil during early French-led specification,

is now taken as meaning Global System for Mobile

communications by the non-French-speaking world.) GSM is

currently being introduced on the European market.

This option has the advantage of using already-existing mobile

infrastructure with a ready and captive market, but at the

expense of limiting channel bit-rate considerably, which in

turn limits the services that can be made available over UMTS.

Some of the technical assumptions of UMTS, such as advanced

security algorithms and distributed databases, would require

new protocols to implement over GSM. GSM would be limiting the

capabilities of UMTS. [BROE93a]

3. Integration with N-ISDN. Like the GSM option above, this

initially limits UMTS's channel bit-rate for services, but has

a distinct advantage over integration with B-ISDN - N-ISDN is

widely available, right now. However, integrating UMTS and

N-ISDN would require effective use of the intelligent network

concept for the implementation of mobile functions, and

modification to existing fixed network protocols to support

mobile access.

Integrating UMTS with N-ISDN makes possible widespread early

introduction and interoperability of UMTS in areas that do not

yet have B-ISDN available. This allows wider market

penetration, as investment in new B-ISDN equipment is not

required, and removes the dependency of UMTS on successful

uptake of B-ISDN for interoperability with fixed networks.

Eventual interoperability with B-ISDN, albeit with

constrictions imposed on UMTS by the initial N-ISDN

compatibility, is not prevented. [BROE93a]

4. Integration with B-ISDN. This scenario was the target of

MONET (MObile NETwork), or RACE Project R2066. Unlike the

above options, B-ISDN's high available bandwidth and feature

set does not impose limitations on the service provisioning in

UMTS. Fewer restrictions are placed on the possible uses and

marketability of UMTS as a result. Development of B-ISDN is

taking place at the same time as UMTS, making smooth

integration and adaptation of the standards to each other


For these reasons, integration of UMTS with B-ISDN has been

accepted as the eventual goal for interoperability of future

fixed and mobile networks using these standards, and this

integration has been discussed in depth. [BROE93a, BROE93b,


At present, existing B-ISDN standards cannot support the

mobile-specific functions required by a mobile system like

UMTS. Enhancements supporting mobile functions, such as call

handover between cells, are needed before B-ISDN can act as

the core network of UMTS.

Flexible support of fixed, multi-party calls, to allow B-ISDN

to be used in conferencing and broadcasting applications, has

many of the same requirements as support for mobile switching,

so providing common solutions to allow both could minimise the

number of mobile-specific extensions that B-ISDN needs.

As an example of how B-ISDN can be adjusted to meet UMTS's

needs, let's look at that mobile requirement for support for

call handover. Within RACE a multiparty-capable enhancement of

B-ISDN, upwardly compatible with Q.2931, has already been

developed, and implementing UMTS with this has been studied.

For example, a UMTS handover can be handled as a multi-party

call, where the cell the mobile is moving to is added to the

call as a new party, and the old cell is dropped as a party

leaving the call, using ADD(_party) and DROP (_party)

primitives. Other mobile functions can be handled by similar

adaptations to the B-ISDN protocols.

The enhancements to B-ISDN Release 2 and 3 that are required

for UMTS support are minimal enough to be able to form an

integral part of future B-ISDN standards, without impacting on

existing B-ISDN work. [BUIT95]

These modifications only concern high-level B-ISDN signalling

protocols, and do not alter the transport mechanisms. The

underlying ATM layers, including the ATM adaptation layer

(AAL) are unaffected by this.


The Intelligent Network (IN) is a means for service providers

to create new services and rapidly introduce them on existing

networks. As the IN was considered useful for implementing

mobility procedures in UMTS, it was studied as part of MONET,

and is now specified in the Q.1200 series of the ITU-T


The intelligent network separates service control and service

data from basic call control. Service control is then

activated by 'trigger points' in the basic call. This means

that services can be developed on computers independent of the

network switches responsible for basic call and connection

control. This gives flexibility to the network operators and

service providers, as well as the potential to support the

services on any network that supports the trigger points.

Eventually, IN can be expanded to control the network itself,

such as handling all UMTS mobile functions. [BROE93a]

Any network supporting the intelligent network service set

will be able to support new services using that service set

easily, making integration of networks easier and transparent

to the user of those services. The intelligent network is thus

an important factor in the integration of B-ISDN and UMTS.

UMTS, B-ISDN and the intelligent network set are all being

developed at the same time, allowing each to influence the

others in producing a coherent, integrated whole. [BUIT95]


In order to be accepted by users as useful and to provide as

wide a variety of services as possible, UMTS needs some form

of interoperabilty or integration with a fixed network.

Integration of UMTS with B-ISDN offers the most flexibility in

providing services when compared to other network integration

options, and constrains UMTS the least.

With the increase in the number of services that will be made

available in UMTS and B-ISDN over present standalone services,

it is unrealistic to develop two separate, and incompatible,

versions of each service for the fixed and mobile networks.

Integrating UMTS and B-ISDN makes the same service set

available to both sets of users in the same timescale,

reducing development costs for the services, and promoting

uptake and use in the market. The intelligent network concept

allows the easy provision of additional services with little

extra development cost. Integrating UMTS with B-ISDN, and with

the intelligent network set, is therefore desirable.

Work on this integration indicates that the mobile

requirements of UMTS can be met by extending existing B-ISDN

signalling to handle them, without significantly modifying

B-ISDN. Integration of UMTS with B-ISDN is therefore

technically feasible.



W. van den Broek, A. N. Brydon, J. M. Cullen, S. Kukkonen,

A. Lensink, P. C. Mason, A. Tuoriniemi,

"RACE 2066: Functional models of UMTS and integration into

future networks",

IEE Electronics and Communication Engineering Journal, June



W. van den Broek and A. Lensink,

"A UMTS architecture based on IN and B-ISDN developments",

Proceedings of the Mobile and Personal Communications

Conference, 13-15 December 1993.

IEE Conference Publication 387.


E. Buitenwerf, G. Colombo, H. Mitts, P. Wright,

"UMTS: Fixed network issues and design options",

IEEE Personal Communications, February 1995.


J. C. S. Cheung, M. A. Beach and J. P. McGeehan,

"Network planning for third-generation mobile radio systems",

IEEE Communications Magazine, November 1994.


S. E. Minzer,

"Broadband ISDN and Asynchronous Transfer Mode (ATM)",

IEE Communications Magazine, September 1989.


T. Norp and A. J. M. Roovers,

"UMTS integrated with B-ISDN",

IEEE Communications Magazine, November 1994.


IBC Common Functional Specification, Issue D.

Race D732: Service Aspects.


R. S. Swain,

"UMTS - a 21st century system: a RACE mobile project line

assembly vision"


Source: Essay UK -

About this resource

This coursework was submitted to us by a student in order to help you with your studies.

Search our content:

  • Download this page
  • Print this page
  • Search again

  • Word count:

    This page has approximately words.



    If you use part of this page in your own work, you need to provide a citation, as follows:

    Essay UK, Integration Of Umts And Bisdn Is It Possible Or Desirable. Available from: <> [26-05-20].

    More information:

    If you are the original author of this content and no longer wish to have it published on our website then please click on the link below to request removal: