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  • P809-GI Mobility in the broadband environment based on IN evolution Deliverable 3 Evolution Strategy for Broadband Mobility Suggested Readers: This Deliverable is directed towards the strategic planning departments of the EURESCOM shareholders organisations and addresses the evolution strategy towards a broadband multimedia network with support of mobility. It is relevant to both fixed and cellular operators, and will facilitate their strategic planning processes. It will help fixed operators to plan a network evolution strategy to offer mobile services, and it will help operators of cellular networks to plan a network evolution strategy for fixed access to cellular services. For full publication June 1999
  • EURESCOM PARTICIPANTS in Project P809-GI are: • BT • Deutsche Telekom AG • FINNET Group • France Télécom • Portugal Telecom S.A. • Swisscom AG • Tele Danmark A/S • Telecom Eireann • TELECOM ITALIA S.p.a. • Telefónica S.A. This document contains material which is the copyright of certain EURESCOM PARTICIPANTS, and may not be reproduced or copied without permission. All PARTICIPANTS have agreed to full publication of this document. The commercial use of any information contained in this document may require a license from the proprietor of that information. Neither the PARTICIPANTS nor EURESCOM warrant that the information contained in the report is capable of use, or that use of the information is free from risk, and accept no liability for loss or damage suffered by any person using this information. This document has been approved by EURESCOM Board of Governors for distribution to all EURESCOM Shareholders. © 1999 EURESCOM Participants in Project P809-GI page 1 (19)
  • Deliverable 3 Evolution Strategy for Broadband Mobility Preface (Prepared by the EURESCOM Permanent Staff) EURESCOM Project P809 was started in January 1998 with the main objective of enabling broadband networks, using IN, to support all forms of mobility. The Project has ended in May 1999. There were 10 companies participating in the Project – Finnet Group, BT, Swisscom, Tele Danmark, Deutsche Telekom, France Télécom, CSELT, Portugal Telecom, Telefónica and Telecom Eireann. The planned size of the Project was 15.6 man-years over 15 months. France Télécom was the Project leader. The first Deliverable from the Project contained descriptions of typical benchmark services that are relevant for broadband mobile multimedia services. In particular it identified the new mobility requirements of broadband multimedia services on the basis of the GMM framework and existing mobility services in the narrowband environment. This gave a good overview of the sort of Broadband multimedia service that is likely to emerge and the demands these services will put on the Intelligent Network to provide these services while supporting terminal and personal mobility. The second Deliverable from the Project has been divided into two volumes. Volume 1 examined the IN architecture issues arising from the benchmark services of Deliverable 1. It also looked at the impact of IP and the terminal requirements. Volume 2 concentrated on the fixed-mobile convergence issues. This third Deliverable of the Project contains an examination of the Evolution Strategy scenarios and options for achieving broadband multimedia mobility. The domain of study considered evolving from both the fixed and mobile networks of today. © 1999 EURESCOM Participants in Project P809-GI page i (x)
  • Evolution Strategy for Broadband Mobility Deliverable 3 page ii (x) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility Executive summary This Deliverable presents possible evolution strategies for fixed and mobile (i.e. GSM-cellular) network operators. With regard to the fixed network, three starting points are identified: PSTN/POTS, N-ISDN, & B-ISDN. Access network issues, which include enabling technologies for broadband access, are addressed. Network evolution scenarios for the business and residential sectors are considered, as well as cordless and Internet access evolution. The integration of IP and IN networks is also discussed. With regard to the evolution strategy for the GSM/GPRS network, technologies such as EDGE, multimode terminals, WAP, Intelligent Agents, Internet, UMTS and BRAN are reviewed. In the past, fixed network operators have considered ways to augment their networks by cordless radio access and mobility procedures in an attempt to emulate cellular services. The standardisation of CTM reflected this philosophy and used IN-based mobility to support DECT radio access. To date, however, commercial success has been elusive and systems have offered limited roaming. An alternative strategy, which extends the roaming capabilities, is to co-operate with a “roaming broker”, i.e., a cellular operator who provides the necessary roaming capability. Cellular services can then be offered through the fixed-network with the benefits of reliability, higher bandwidth, reduced cost and a single number for the customer. However, this latter strategy assumes that the mobile services are cellular services and as a consequence brings to the forefront the technologies for creating cellular services. In a press release from May 12, 1999, the GSM Association claimed to represent the interests of 347 GSM, Satellite and 3G network operators, regulators and administrative bodies from 133 countries and areas of the world. It was further claimed that GSM services are provided to more than 160 million customers of the world or 65 percent of the world's total market for digital wireless communications. Of note, major satellite operators joined the GSM Association on April 20, 1999 to pioneer the concept of GSM satellite technology. The ETSI partner project 3GPP is specifying UMTS, and is mandated to build upon the GSM platform. It therefore appears that UMTS is poised to become the world standard for 3 rd Generation mobile communications by virtue of its key role in the GSM-operator evolution path. To date, all licensed 3rd Generation operators have joined the GSM Association. The fixed network will have an important role to play in completing this picture and will provide access to future GSM/UMTS services. Integration of entertainment services will be the final step in the move towards true broadband mobility. Currently, the commercial driver for multimedia traffic is the Internet. IP-based services provide the business case for mobile multimedia and justify the evolution towards 3rd Generation systems. In the fixed network, technologies such as xDSL will provide the necessary access speeds to offer future GSM/UMTS services, while IP and ATM will provide the required switching. In the cellular environment, technologies such as EDGE, HSCSD, GPRS and UMTS will shape the characteristics of future mobile services. Intelligent Networks have traditionally provided centralised service control in fixed networks. More recently, the CAMEL system has extended these capabilities to the mobile arena. However, with the introduction of processing into terminals and application servers, intelligence becomes decentralised. In considering the evolution of network intelligence for mobile service provision, technologies such as WAP and Intelligent Agents offer solutions for advanced cellular service provision using distributed processing. © 1999 EURESCOM Participants in Project P809-GI page iii (x)
  • Evolution Strategy for Broadband Mobility Deliverable 3 In conclusion, there are several starting points, many technologies, and alternative strategies for evolving towards broadband mobility. Some EURESCOM partners already operate cellular networks while others do not. Regulatory constraints may preclude certain evolutionary options for some operators. This Deliverable, therefore, does not mandate specific technologies or strategies, rather it seeks to be inclusive of as many options as is reasonable. It will help EURESCOM shareholders to identify an appropriate evolutionary path for their own network towards broadband mobility in accordance with their business goals and local regulatory conditions. page iv (x) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility List of authors Harri Hansén AF Ari-Pekka Kanerva AF Paul Glennon BT Geoff Richman BT John Charles Francis CH Narcisse Mavoha CH Stephan Robert CH Niels Kristian Kristansen DK Finn Kristoffersen DK Hartmut Brandt DT Petia Todorova DT Claudine Guedj FT Rached Hazem FT Giuseppe Plagenza IT Gustavo Basto PT Jaime Ferreira PT Ignacio Berberana TE Gaspar Moreno TE Lourdes Moreno de Barreda TE Gaspar Valdivia TE Richard Collins TI Andrew Kelleher TI © 1999 EURESCOM Participants in Project P809-GI page v (x)
  • Evolution Strategy for Broadband Mobility Deliverable 3 Table of contents Preface...........................................................................................................................................i Executive summary.....................................................................................................................iii List of authors...............................................................................................................................v Table of contents.........................................................................................................................vi Figures........................................................................................................................................vii List of Acronyms......................................................................................................................viii 1 Introduction...............................................................................................................................1 2 Target System Requirements....................................................................................................3 3 Evolution Strategy for Fixed Network Operator......................................................................7 3.1 Fixed network evolution start-points.................................................................................7 3.1.1 Scenario 1 - PSTN/POTS starting point.....................................................................7 3.1.2 Scenario 2 - N-ISDN starting point............................................................................8 3.1.3 Scenario 3 - B-ISDN starting point.............................................................................9 3.2 Network evolution strategy..............................................................................................11 3.2.1 Access network issues...............................................................................................11 3.2.2 Enabling Technologies .............................................................................................12 3.2.3 Addition of BRAN access.........................................................................................12 3.3 Network Evolution Scenarios..........................................................................................13 3.3.1 Evolution in the business sector...............................................................................14 3.3.2 Evolution in the residential sector............................................................................14 3.3.3 Cordless evolution scenario......................................................................................15 3.3.4 Internet access evolution...........................................................................................16 3.3.5 Integration of IP and IN networks............................................................................19 3.4 Fixed network strategy conclusions.................................................................................20 4 Evolution Strategy for Mobile Network Operator..................................................................23 4.1 Starting point: GPRS........................................................................................................23 4.1.1 Enabling Technology: EDGE Access.......................................................................23 4.1.2 Enabling technology: Multimode terminals.............................................................24 4.1.3 Enabling Technology: WAP.....................................................................................24 4.1.4 Enabling Technology: Intelligent agents..................................................................25 4.1.5 Enabling Technology: Internet QoS.........................................................................25 4.2 Migration paths.................................................................................................................26 4.2.1 Scenario 1: GSM/GPRS-UMTS-BRAN...................................................................26 4.2.2 Scenario 2: Licence-exempt telecom network.........................................................27 4.2.3 Scenario 3: Licence-exempted access to IP core network.......................................28 4.2.4 Scenario 4: Evolution utilising fixed IP-access technologies..................................28 4.3 Conclusions......................................................................................................................29 5 Common Requirements and Conclusions...............................................................................33 References..................................................................................................................................36 page vi (x) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility Figures Figure 1: Scenario 1: PSTN/POTS starting point........................................................................7 Figure 2: Addition of UMTS radio access...................................................................................8 Figure 3: Scenario 2: N-ISDN starting point...............................................................................8 Figure 4: N-ISDN evolution scenario..........................................................................................9 Figure 5: Scenario 3: B-ISDN starting point.............................................................................10 Figure 6: B-ISDN evolution scenario........................................................................................10 Table 1: Some technologies available for access network upgrading......................................12 Figure 7: Adding BRAN access to the evolved fixed networks................................................13 Figure 8: Target system using IN with mobility support..........................................................13 Figure 9: Access network for medium and large businesses based on SDH rings...................14 Figure 10: Integrated access network serving residential and small business customers........15 Figure 11: CTM evolution towards UMTS...............................................................................16 Figure 12: Today’s access to internet........................................................................................17 Figure 13: ‘Always-on’ broadband access.................................................................................17 Figure 14: ‘Always-on’ broadband access with mobility..........................................................18 Figure 15: Long-term vision......................................................................................................19 Figure 16: Signalling interfaces in PSTN to H.323 interworking.............................................19 Figure 17: Interworking of PSTN and H323 networks with IN support...................................20 Figure 18: Interworking with Mobile Networks (Cellular).......................................................20 Figure 19. GSM/GPRS network.................................................................................................23 Figure 20. GSM/GPRS access to IP networks (ca. 100 kbit/s).................................................26 Figure 21. UMTS Phase 1: UTRA access via the GPRS network (few hundred kbit/s) .........27 Figure 22. UMTS phase 2: UTRA access via the UMTS CN (few hundred kbit/s)) ..............27 Figure 23. Unregulated access (BRAN/TDD-UMTS) via the UMTS core network (up to 20 Mbit/s).........................................................................................................................................28 Figure 24. BRAN access directly to IP based core network (up to 20 Mbit/s). ......................28 Figure 25: Long-term vision......................................................................................................29 Table 2: Road map of mobile data services .............................................................................31 © 1999 EURESCOM Participants in Project P809-GI page vii (x)
  • Evolution Strategy for Broadband Mobility Deliverable 3 List of Acronyms 3G 3rd Generation 3GPP 3rd Generation Partner Project 8PSK Octantal Phase Shift Keying AAA Authentication, Authorisation and Accounting ADSL Asymmetric Digital Subscriber Line AF Assured Forwarding API Application Programming Interface BCCH Broadcast Control Channel BRAN Broadband Radio Access Network BSC Base Station Controller BSS Base Station Subsystem BTS Base Transceiver Station CAMEL Customised Application for Mobile network Enhanced Logic CATI Charging and Accounting for the Internet CATV Community Antenna TV CGI Common Gateway Interface CPU Central Processing Unit CTS Cordless Telecommunication System DECT Digital Enhanced Cordless Telecommunications Diffserv Differentiated services DNS Domain Name Service DSS1 Digital Signalling System 1 (ISDN access protocol) DSS1+ Enhanced DSS1 DSS2 Digital Signalling System 2 (B-ISDN access protocol) EDGE Enhanced Data rates for GSM Evolution e-mail Electronic Mail ETSI European Telecommunication Standards Institute FDD Frequency Division Duplex FT Fixed Terminal GGSN Gateway GPRS Support Node GK Gatekeeper GPRS General Packet Radio System GSM Global System for Mobile communications GSM MoU GSM Memorandum of Understanding G-UMTS GSM-network based UMTS page viii (x) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility GW Gateway HA Home Agent HCS Hierarchical Cell Structure HDSL High data-rate Digital Subscriber Line HLR Home Location Register HTML Hyper Text Mark-up Language HTTP Hyper Text Transfer Protocol IETF Internet Engineering Task Force IMT-2000 International Mobile Telecommunications IN Intelligent Network INAP IN Application Part (of ITU-T Signalling System no. 7) Intserv Integrated Services IP Internet Protocol IPv4 Internet Protocol version 4 (current version of IP) IPv6 Internet Protocol version 6 (new version of IP) ISDN Integrated Services Digital Network ISP Internet Service Provider ISUP Integrated Services User Part (of ITU Signalling System no. 7) ITU International Telecommunications Union ITU-T ITU Telecommunications Standardisation Sector (formerly CCITT) I-UMTS ISDN/PSTN-network based UMTS IWU InterWorking Unit LMDS Local Multipoint Distribution Services Mbit/s Megabits per second (1 048 576 bits per second) MS Mobile Station MSC Mobile Services Switching Centre MSS Mobile Satellite Service MT Mobile Terminal NE Network Element NMF Network Management Forum NSS Network and Switching Subsystem OMG Object Management Group ONU Optical Network Unit PC Personal Computer PIG PSTN/Internet Gateway PNO Public Network Operator © 1999 EURESCOM Participants in Project P809-GI page ix (x)
  • Evolution Strategy for Broadband Mobility Deliverable 3 POP Point of Presence PSTN Public Switched Telephone Network QoS Quality-of-Service RSVP Resource Reservation Protocol SGSN Serving GPRS Support Node SLA Service Level Agreement SMS Short Message Service SSL Secure Socket Layer TD-CDMA Time Division - Code Division Multiple Access TDD Time Division Duplex TDMA Time Division Multiple Access TINA-C Telecommunications Information Networking Architecture Consortium TUP Telephone User Part UMTS Universal Mobile Telecommunications System URL Uniform Resource Locator UTRA UMTS Terrestrial Radio Access UTRAN UMTS Terrestrial Radio Access Network VDSL Very high data-rate Digital Subscriber Line VHE Virtual Home Environment VLR Visitor Location Register VPN Virtual Private Network WAP Wireless Application Protocol WCDMA Wide-band Code Division Multiple Access WLAN Wireless Local Area Network WML Wireless Mark-up Language WTLS Wireless Transport Level Security WTP Wireless Transaction Protocol WWW World Wide Web xDSL (A- / H- / V- ) Digital Subscriber Line page x (x) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility 1 Introduction Broadband multimedia services, which can be accessed from fixed and mobile terminals, have considerable market potential. International standards are being developed to provide for such services and several technologies will soon be available. IMT-2000 and UMTS requirements are the basis of the target network. UMTS, which will be operational in 2002, gives a time frame for network evolution. These developments offer opportunities and present challenges for network operators. Systems capable of supporting mobile multimedia services require very large investments. Customers will only invest in expensive terminals if these offer attractive new services of the highest quality and an acceptable price. Operators will have to develop their core and access networks to meet these demands. This Deliverable gives scenarios for network evolution. Two starting points have been selected: one is based on existing narrowband networks with enhanced IN, ISDN and xDSL technologies and the other on IP and cellular GSM developments. Demand for WWW services based on the Internet Protocol (IP) has been spectacular. These services are now used by tens of millions of customers and can be regarded as the first truly multi-media services. The Web was originally used for browsing but it now provides IP-based interactive, real-time services, such as audio and video broadcasts, telephony and video telephony. Evolution towards UMTS must take account of the present GSM infrastructure and the large existing customer base. UMTS will evolve from GSM. There are several key issues: • UMTS and GSM must interwork seamlessly. Handsets must be able to switch between networks. • GSM and UMTS will co-exist for a considerable period of time, each system with its own market segment but sharing a common infrastructure as far as possible. • UMTS will focus, initially, on a market segment requiring high data-rates. There are parallels with the present General Packet Radio System Services (GPRS). Enhanced Data rates for GSM Evolution (EDGE) are discussed at the end of this Deliverable. This will offer rates of 384kbit per second, enabling second generation operators to maintain a competitive position against third generation operators. © 1999 EURESCOM Participants in Project P809-GI page 1 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 page 2 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility 2 Target System Requirements The market for multimedia services is growing. It is influenced by the falling cost for personal computers, increasing acceptance of IT in the office and at home together with the growth of Internet with electronic commerce applications and corporate Intranets. The demand for rapid and remote access to information is increasing, driven by higher productivity and flexibility requirements, the need of reducing “dead” time. These trends would certainly influence the development of future mobile communications, which, hitherto, have been focused on the provision of voice services. Support for these market places requirements on the target network. • Compatibility and full routing capability for IPv4 and IPv6. • IP portability over IMT-2000 (UMTS) networks and fixed networks. • Various services (Push, Pull, Multicast, etc.). • Packet mode bearer up to 2Mbps (initially 384kbps). • Support for both packet and circuit switched services, such as Internet (IP) traffic and videoconference. High data rate communication services and asymmetric data transmission. • Public and private Internet access services should be supported. • In Public Internet Access Service: Home agent resides in the service provider network, and authentication and authorisation information is held and processed by any of the service provider network, home ISP, or private network. • In Private Network Internet Access Service: Home agent resides in an external network, and authentication and authorisation information is held and processed in the external network. The external network is usually behind a firewall, and possibly has a pool of non-routable and non-unique addresses. Users expect to be able to access their own personalised services in a consistent way no matter where they are, e.g. at home, in the office, on the move. This places mobility and service related requirements on the target system. • Terminal mobility, personal mobility, and service portability • Global roaming and roaming with 2G systems • Mobility over different radio systems • Support multiple public/private/residential operators in the same locality. • Interconnection to other mobile or fixed users. Capable of providing service to fixed users. • National and international roaming. • Mobility needs to be based on the users, not the device used by the user. The future of mobile telephony is now being determined by the global standardisation work being conducted by public authorities and the industry. In Europe, ETSI is working on the UMTS which will become a member of an International Telecommunication Union (ITU) IMT-2000 specifications. The target system should offer flexibility in the support of the following network requirements • Network scalability © 1999 EURESCOM Participants in Project P809-GI page 3 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 • Rapid service introduction • VHE (Virtual Home Environment) and operator specific services • New charging mechanism, data volume vs. time. • Support for several simultaneous connections. A user should for example be able to browse Internet and simultaneously receive a fax or a phone call. • The network should allow for seamless roaming between heterogeneous wireless and fixed access networks. And provide seamless service when subscriber roaming between all network systems. • This seamless service should be possible by maintaining a formal customer-service provider relation with only one Service Provider. It means that a roaming user should only need a single subscription to access home network services. • The network should avoid triangle routing as much as possible. Triangle routes (which contain routing anchor point) can be established at two points: 1) at the home network as defined in mobile IP and 2) at the foreign network]. The network needs to support a mechanism to allow or disallow triangle routes, e.g., a policy that wants to hide knowledge of where the user is located. The target system must provide a user with access to broadband multimedia services from different access points and while on the move. The Quality of Service perceived by the User and consistency of presentation imposes requirements on the target system. • The network should provide Quality-of-Service (QoS) support • Speech quality comparable to fixed network and high quality for audio, data, image, and video • Voice quality comparable to wireline. • Soft handover • QoS (Quality of Service) indication/negotiation (CBR, VBR, ABR, UBR) • End to end QoS support is essential for business and real-time applications such as Internet telephony and on-line video communications. • Differentiated services (Diffserv RFC 2474 [4] and RFC 2475 [5]) is a new approach for QoS in the Internet, however this scheme is not completely adapted to mobile environments, so some kind of integration of Diffserv and Mobile IP protocols is required. The target system shall satisfy the following requirements for security and privacy. • Protection from impersonation. • Protection of user and service profile from malicious attacks. • Privacy of communications and user location. • Security comparable to PSTN/ISDN. • Robust Authentication, Authorisation and Accounting services (AAA servers and protocols) should be supported The radio-link AAA services should be separated from the data (e.g. IP address) resource AAA services. Also, complete AAA support services (e.g. broker services, key distribution, etc.) should be provided. page 4 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility There may be cost advantages in accessing mobile multimedia services through the fixed network and the Virtual Home Environment (VHE) could unify service provision across access media. These cost advantages may be enhanced through the deployment of a cost-effective network technology and will place requirements on the target network. • Multivendor environment, via open (standard) interfaces • Effective use of transmission facility and advanced switching technologies • Support a broad range of applications, e.g. cellular, WATM, … • High spectral efficiency • Support for multiple cell layers (Hierarchical Cell Structures, HCS). • Coexistence and interconnection with satellite and support for compatible multiple access schemes for terrestrial and satellite components. • A phased approach for data rates up to 2Mbps. • The network infrastructure should be access independent and support a wide range of mobile stations and network configurations • As current wireless networks evolve, the target network should support all wireless access (GSM, DECT, UMTS, etc.). Users should be able to roam between different access types via a mobile device that supports access specific PC cards which provide the appropriate 'layer 2' access. • The network will support dynamic and static home address configurations, allow for dynamic assignment of the Home Agent (HA), as a way to avoid triangle routing, and support multiple simultaneous IP addresses. • The current networking protocols that perform the mobility management functions specific to the heterogeneous technologies should evolve into a common protocol. • Billing and accounting functions must be supported. • Additional billing and accounting mechanisms must be provided when a mobile node visits a foreign network and requests to use the Service Level agreements (SLA) of the foreign network. • Also, a protocol for exchanging SLAs including Virtual Private Network (VPN) and QoS parameters between users and ISPs as well as between ISPs is needed. Some work is in progress in CATI group of Internet Engineering Task Force (IETF). © 1999 EURESCOM Participants in Project P809-GI page 5 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 page 6 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility 3 Evolution Strategy for Fixed Network Operator From a fixed network operator perspective, it is very important to evolve towards UMTS and IMT-2000, to take benefit of previous and current infrastructure investments. That means to continue the evolution based on network investments already made. This typically includes N-ISDN Local Exchange, ATM transport core network, IN services (CS-1 and CS-2), and/or IP access to the Internet. Also current or planned investments in the near future should be considered in combination with the evolution scenarios. These investments typically include: fixed line xDSL access, deployment of DECT spots, B-ISDN Local Exchanges, IN-based broadband multimedia control and/or IN-based IP service control. The core network evolution is separated in two phases. The first phase considers short-term evolutions of the fixed core network from the three starting points. The evolution shown in these scenarios is consistent with the 3GPP UMTS evolution path. The second phase proposes an extension that may be applied in the long term from these scenarios. 3.1 Fixed network evolution start-points Three different types of fixed access core networks have been selected as starting points for the network evolution scenarios towards a target core network supporting broadband services and mobility. The selected starting points are considered to represent the most common public fixed network types. 3.1.1 Scenario 1 - PSTN/POTS starting point The first starting point is POTS terminals connected to the PSTN as shown in Figure 1. The following assumptions have been made: • The fixed terminal (FT) is a POTS terminal. • The core network uses N-ISDN for transport and switching • IN is not implemented FT=POTS MF4 ISUP FT PSTN PSTN/N-ISDN X.25 X.25 Packet Network IP IP IP networks Core networks Other networks Figure 1: Scenario 1: PSTN/POTS starting point A first step in the evolution of a PSTN core network that satisfies some of the requirements of a target system is illustrated in Figure 2. The evolution is based on © 1999 EURESCOM Participants in Project P809-GI page 7 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 installation of a UMTS Base Station Sub-systems (BSS) and introduction of IN in the core network to provide support for terminal and personal mobility. Also handover is unlikely to be supported in this scenario. An InterWorking Unit (IWU) is introduced in the access point Iu, to separate circuit switched and packet data traffic in the core network. From the UMTS BSS over the Iu interface xDSL modem technology may be used over the copper local loop. The use of xDSL will offer a bandwidth of more than 300kbit/s. IN FT=POTS (mobility support) FT ISUP N-ISDN UMTS BSS N-ISDN BTS RNC Iu MT IWU Packet network BTS RNC Packet Network xDSL IP IP IP networks Core network with mobility support Other networks Figure 2: Addition of UMTS radio access 3.1.2 Scenario 2 - N-ISDN starting point This starting point, shown in Figure 3 is based on N-ISDN with the following assumptions: The FT is an ISDN terminal, with DSS1 (Q.931) [2] access signalling. The core network uses N-ISDN transport and switching. The provision of IN support optional. IN FT=ISDN BA ISUP FT N-ISDN N-ISDN/IN X.25 X.25 Packet Network IP IP IP networks Other networks Core networks Figure 3: Scenario 2: N-ISDN starting point As a first step to provide mobility, IN with mobility support may be added to the core network. This is illustrated in Figure 4. This update of the core network provides the user with terminal mobility via fixed access provided that a terminal/user registration page 8 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility procedure is introduced. The maximum bandwidth that can be supported over ISDN BA is 144 kbit/s. IN FT=N-ISDN BA (mobility support) N-ISDN evolution ISUP Step 1: Addition of FT ISDN mobility support N-ISDN X.25 Packet network Packet Network IP IP IP networks Core networks Other networks FT = ISDN BA Step 2: Addition of IN (mobility support) UMTS radio access FT ISUP ISDN DECT / UMTS BSS Iu N-ISDN X.25 BTS RNC MT IWU Packet network BTS RNC Packet Network IP IP IP networks Core network with mobility support Other networks Figure 4: N-ISDN evolution scenario In a next step the N-ISDN network may be updated with radio access. This may be in terms of a UMTS radio access (as illustrated in Figure 4) or DECT. To support UMTS the DSS1+ protocol used over the user network interface must be enhanced. The support of mobility in this scenario is still limited so that only mobility within the DECT / UMTS BSS coverage area is supported, i.e. no handover support is assumed. However a UMTS/DECT terminal may roam into another subsystem assuming the necessary access rights have been granted. 3.1.3 Scenario 3 - B-ISDN starting point This starting point for fixed networks is B-ISDN based on ATM. Broadband ATM networks, shown in Figure 5 provide the infrastructure to facilitate integration of telecommunication and computer communication for the provisioning of advanced multimedia services to the user. Within the target of 3G UMTS integration with B- ISDN based on ATM transport, integration with Intelligent Network concept and support of numerous and divers radio interfaces have to be provided. The assumptions for the B-ISDN based network are: • B-ISDN core network with ATM transport. • Fixed line N- or B-ISDN terminals, with DSS1/2 (Q.931[2], Q.2931[3]) access signalling. © 1999 EURESCOM Participants in Project P809-GI page 9 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 • Optional support for IN. FT=N-/B-ISDN IN B-ISUP FT B-ISDN B-ISDN/IN X.25 X.25 Packet Network IP IP IP networks Other networks Core networks Figure 5: Scenario 3: B-ISDN starting point From the B-ISDN starting point Figure 5, evolution steps are illustrated in Figure 6. The first step will offer personal mobility and terminal mobility via fixed access. The core B-ISDN network is extended with IN functionality with mobility support. The personal user profile is stored in the MSDF of the IN. In order to support terminal mobility via fixed access the DSS2 access protocol has to be extended, in the figure indicated as DSS2+. These enhancements lead to INAP extensions too. IN (mobility Support) FT = B-ISDN B-ISDN evolution INAP B-ISUP DSS2+ FT Step1: Addition of B-ISDN mobility support B-ISDN X.25 Packet Network Packet Network IP IP IP networks Core networks Other networks FT = B-ISDN IN Step 2: Addition of (mobility Support) UMTS radio access FT INAP B-ISUP+ DSS2+ B-ISDN UMTS BSS B-ISDN BTS RNC Iu X.25 MT IWU Packet Network BTS RNC Packet Network IP xDSL IP IP networks Core networks Other networks Figure 6: B-ISDN evolution scenario page 10 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility In the second step radio access may be added to the B-ISDN network. The fixed terminal access is extended with mobile access using a mobile terminal (MT). The B-ISDN network is updated with radio access via an InterWorking Unit (IWU). The IWU is assumed to support both DSS2 and V.5B interfaces. The transport from the access network to the IWU can be xDSL. In this example, access to the Iu interface is based on xDSL technology. 3.2 Network evolution strategy Telecommunication networks are evolving to provide users with access to a diverse range of services which are available at all times from any location and on personalised terms and conditions. Networks providing entertainment, telephony and data services are converging to multiple interacting networks rather than a single all-purpose network. We do not require a single unique architecture but rather a framework in which different elements can coexist and work together. It is convenient to divide the network into four domains as described in the ETSI GMM Report [1] covering the terminal, access network, core network and applications. The access segment has traditionally been the most difficult part of the network to change and upgrade. Whilst core network and terminal technologies have been transformed in recent decades, the access network has changed little, although the access part of the traditional telephony network accounts for about one third of all network costs. 3.2.1 Access network issues The existing network is predominantly composed of cable pairs. These have limited bandwidth and the carrying capacity of copper decreases with line length. The main impact of broadband demand is that effective line lengths are greatly reduced. Operators have invested heavily in copper and, in order to obtain an adequate return on that investment will wish to maximise the use of the copper access network. This is a major issue as they plan for broadband mobility. A second factor is the convergence of CATV distribution systems and the existing voice and data networks. CATV operators are beginning to offer traditional network services and will pose a challenge to traditional network operators. The economics of network provision will dictate the use of a single bearer into the home, giving access to all services. It is therefore imperative that operators integrate their access networks as far as possible. The requirements of the business and residential segments differ and will continue to diverge. Each of these segments may require a different evolution strategy. The business segment: The legacy system is predominantly copper pairs. These must be exploited to the maximum extent possible. Optical fibre is now being used extensively and will be needed increasingly where copper pairs are inadequate. The residential segment: The residential segment consists, at present, of a fixed telephony copper based network and mobile telephony networks. CATV networks have been developed independently by the entertainment and broadcasting sectors. Telephony, information, data and entertainment networks are now converging. Internet access is an important ‘driver’. Very high bit-rates will be required for future multi-media internet services such as video transmissions and interactive shopping. © 1999 EURESCOM Participants in Project P809-GI page 11 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 3.2.2 Enabling Technologies The core issue is the provision of increased bandwidth, while utilising existing copper plant as much as possible. Broadband networks will have access bandwidths in the range 2 to 155Mbit/s. A number of technologies have been developed which can provide increased bandwidths over copper-based access networks. The principal ones are listed in Table 1. Technology Bandwidth Distance Shared medium ADSL 2 - 8 Mbit/s 2-4 km No ISDN (basic access) 128 kbit/s 2-4 km No ISDN (primary access) 2 Mbit/s 2-4 km No VDSL 52 Mbit/s 1 km No Cable modem 10 Mbit/s 1 km Yes Wireless (BRAN) 144 kbit/s -155 Mbit/s 3 km Yes Table 1: Some technologies available for access network upgrading Local Multi-Point Distribution Services (LMDS), currently under test, use frequencies in the 28GHz to 40GHz range. More flexibility in spectrum allocation will be required for wireless applications. This will mean replacing equipment that is operating at present on frequency bands that have been reallocated to other services. The technologies listed in Table 1 can be used in conjunction with SDH fibre rings to integrate access networks. The overall strategy is to gradually replace the existing ‘tree and branch’ copper-based networks with fibre and radio-based SDH rings. Future access networks will be based on ATM technology and SDH rings. 3.2.3 Addition of BRAN access The above scenarios all indicate evolutions possible in the short term towards UMTS, while the following evolution will be possible only in a second phase when the Broadband Radio Access Network (BRAN) standardisation is completed. BRAN denotes a number of technologies being suitable for the implementation of broadband radio access networks. The technologies are described in Technical Reports (TRs) produced by ETSI Project (EP) BRAN. These networks are intended to support a variety of core networks, including those based on ATM and IPv4/IPv6. BRAN networks provide point-to-point, point-to- multipoint or multipoint-to-multipoint access at a typical rate of 25 Mb/s or more. From the last steps of the above fixed network evolution scenarios BRAN access may be added. This scenario shown in Figure 7 will be the last step in the evolution towards a fixed network supporting the target system requirement for broadband multimedia services and mobility. page 12 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility FT = POTS / FT IN N-ISDN / B-ISDN (mobility support) N-ISDN UMTS BSS Iu BTS RNC MT UMTS CN ATM BTS RNC IP BRAN IP networks MT Core network Other networks Figure 7: Adding BRAN access to the evolved fixed networks The radio and fixed access may support a number of terminals. The UMTS core network will provide wide area transport for all the access types. Mobility control may be supported in the ATM switches, in mobile servers and in the IN with mobility support. Protocol extensions are needed in order to fulfil all the mobility requirements. For a fixed network operator using IN, the target system to provide broadband services in a mobile context can be as shown in Figure 8. IN with mobility support Generic IN mobility Generic IN service management for both control for both broadband services and broadband services IP services and IP services FT=UMTS BSS BTS RNC Iu N-ISDN MT ATM UMTS CN IP networks BTS RNC xDSL Core network with mobility management Other networks Figure 8: Target system using IN with mobility support 3.3 Network Evolution Scenarios The evolution of the fixed network will be performed in parallel with a still closer integration with other networks. Important evolutions of related networks and integration with the evolution of the fixed network are addressed in this section. In the current situation, each network has a separate access component. For cost effective operation in a GMM environment, common access networks must be used where possible. SDH ring technology offers a means to evolve towards this. In the following approach, SDH rings draw together existing systems and combine sections of various access networks. © 1999 EURESCOM Participants in Project P809-GI page 13 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 When a ring is introduced, large portions of copper loops become redundant. Short lengths of existing pairs can be used for the high bandwidth transmissions between the terminal and, for example, a roadside cabinet giving access to the ring. The redundant sections of the shortened lines need not be discarded. They will be available for reuse by new customers. The access bearers can be integrated by introducing SDH rings in the access network. In the first phase, the fixed and mobile narrow band access networks can be rationalised using an SDH ring to connect fixed narrowband networks and mobile networks. 3.3.1 Evolution in the business sector In large industrial applications, a completely new access network will be required and, in view of the large traffic levels involved, will be economically feasible. With small to medium industrial applications the existing copper network must be exploited to the fullest extent possible. For small to medium businesses, the retention of portion of the copper loop will be feasible. A possible configuration is shown in Figure 9. A physical Point of Presence (POP) will be required in the area to be served. The access network is terminated at the POP. The fibre optic ring will encircle the locations to be served. Multi-port optical fibre closures will enable spurs to be connected to the ring. Copper pairs will be adequate for spurs over short distances. Pre mis es A Pre mises B, etc. Core Networks: POP Narro w & broadband, SDH ring fixed & mobile Subs criber mu x s pur Figure 9: Access network for medium and large businesses based on SDH rings Fibre connections (or another SDH ring network) will be required to connect the POP to each of the serving narrow and broadband networks. The use of SDH rings provides security, because a premise has access to the POP in two directions. Only simultaneous failures in both directions will disrupt service. Redundancy over the spur can be provided by using duplicate copper pairs on alternative routes. 3.3.2 Evolution in the residential sector The residential network is much more dispersed than in the business case and requires a different approach. Some of the relevant technologies needed in this sector are listed in Table 1. Migration can be achieved in several steps: 1. The existing primary cross connection cabinets should be replaced by flexible access multiplexers. 2. Primary copper cable routes should be replaced by fibre. 3. Distribution cables should be replaced by fibre. page 14 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility Each of these steps progressively will reduce the overall copper line lengths, until they are sufficient to carry the high bit-rates required for broadband services. The following steps may also be implemented on the path to the target access network: 1. Roadside cabinets should be installed: ‘Fibre to the kerb’ provision. 2. Closure of SDH rings between cabinets will give the configuration shown in Figure 10. 3. CATV can be integrated with voice and data services at the local exchange (Figure 10). 4. ‘Fibre to the home’ provision will eliminate copper pairs altogether. CATV Fixed customers DECT ONU customers POP SDH Local exchange ring Small businesses Radio base station Rural customers Figure 10: Integrated access network serving residential and small business customers The access network in the figure uses an SDH ring. The configuration includes fixed customers, rural customers served by radio, and DECT customers. (‘ONU’: Optical Network Unit). The ultimate target access network will have fibre to the home, integrating narrow- band, broadband and cable TV services. Security will be incorporated using managed SDH rings providing diversity for all customers. A radio overlay network will provide mobility in urban areas. Radio access systems will predominate in isolated rural areas. 3.3.3 Cordless evolution scenario The scenario in Figure 11 has as a starting point a fixed N-ISDN Core Network with IN capabilities Concerning the Radio Access Network wireless access is provided for CT2 or DECT users based on the IN Cordless Terminal Mobility (CTM) service. The CN provides switching and transmission functions, including call control. Support of mobility functions is provided by the service control network based on IN. The services offered during the different evolutionary steps are given accordingly. The CTM service evolves in phases with the evolution of IN in terms of capability sets (CSs). © 1999 EURESCOM Participants in Project P809-GI page 15 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 IN CS-3 provides the means for integration with B-ISDN offering a wide range of advanced multimedia services. From the B-ISDN point of view, protocols and interfaces are described in B-ISDN CS-3. The integrated IN/B-ISDN core network based on IN CS-3/ B-ISDN CS-3 architecture offers the full range of mobility functions, e.g. personal mobility, terminal mobility, location management, roaming, etc. This step encompasses the introduction of the B-ISDN User Network Interface (UNI) to the access network and the introduction of UMTS terminals supporting the UMTS radio interface. Services -C d s Tl poy o l s e hn r e e -Ehne C d s nac d o l s r e IN/B-ISDN Fl U T u M l S -F e N sr i e i d B e cs x v -F e B s r i e i d B e cs x v sr i e e cs v sr i e e cs v -N I s r i e e Ne c s w v -I sr i e Ne c s v Ri ao d C2 T C2 T+ UT M S A es c s c DC ET DC+ ET Ri ao d Nw k e o t r CM T-1 CM T-2 C to orl n Tr e a t g Nw k e o t r UT M S I C- NS 2 I C- NS 3 I C- NS 4 T npr r so a t NSN - D I BSN - D I BSN - D I C- S 2 C-S3 Nw k e o t r Figure 11: CTM evolution towards UMTS 3.3.4 Internet access evolution The method used today to access the Internet backbone is through a call to a PSTN/internet gateway (PIG) provided by an internet service provider (ISP). The essential network components to provide this access are a voice-band modem e.g. V.90 56kbit/s, using PSTN transport and switching to access an ISP Gateway (with a bank of voice-band modems) to the internet backbone. This arrangement supports ‘on-demand’ access to the internet, i.e. the user dials the access number of the ISP and a bearer is maintained throughout the internet session, irrespective of any packet transfer. Terminal mobility is supported by using alternative network access points and possibly different access numbers. Home WWW pages would have to be stored on space provided by the ISP to make them always available to other WEB browsers. page 16 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility FT Voice- LEX band TEX PSTN modem PSTN / ISDN Voice- band IP network modem ISP Gateway Core network Other networks Figure 12: Today’s access to internet ‘Always-on’ broadband access In this scenario, the essential network components to provide this access are: • High capacity modem (e.g. xDSL) to carry bearer and signalling over copper line plant; • Packet network transport and routing; • ISP Gateway to the internet backbone. This arrangement supports ‘always on’ access to the internet, i.e. the terminal is always connected to the internet backbone irrespective of any requirement to transfer packets. Terminal mobility is unlikely to be supported as this is not compatible with the ‘always on’ feature. Home WWW pages could be stored on space provided by the ISP or on the user’s terminal. FT LEX TEX N-ISDN Circuit switched network PIG Copper line FT XDSL XDSL ISP Gateway Internet modem modem Packet Network xDSL Core network Other networks Figure 13: ‘Always-on’ broadband access ‘Always-on’ broadband access with mobility In this scenario, the essential network components to provide this access are: • Broadband base-station ( e.g. UMTS, blue-tooth, DECT, wireless-LAN); • High capacity modem (e.g. xDSL) to carry bearer and signalling over copper line plant; • Mobility support using Home and Mobility servers. © 1999 EURESCOM Participants in Project P809-GI page 17 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 This arrangement supports ‘always on’ access to the internet provided the terminal is in range of a radio access, i.e. the terminal is always connected to the internet backbone irrespective of any requirement to transfer packets. Location and authentication procedures required for terminal mobility are supported through call unrelated signalling mechanisms to the mobility server. The interface between the Home and Mobility servers is the same as for UMTS HLR-VLR. Home WWW pages would have to be stored on space provided by the ISP to make them always available to other WEB browsers. FT LEX TEX N-ISDN Circuit switched Network Copper line Mobility Server Home Server MT Base- XDSL XDSL Internet IWU station modem modem Packet Network xDSL Core Network with Security and Mobility Management Other networks Figure 14: ‘Always-on’ broadband access with mobility Long-term vision In this scenario, the essential network components to provide this access are: • Broadband base-station ( e.g. UMTS, Blue-Tooth, DECT, wireless-LAN); • High capacity modem (e.g. xDSL) to carry bearer and signalling over copper line plant; • UMTS core network introduced; • Mobile IP used for mobility (Home Agent and Foreign Agent) The introduction of the UMTS core network eliminates the need for the circuit switched network to handle any telecom traffic from the terminal. page 18 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility FT LEX TEX N-ISDN Circuit switched Network Copper line Mobility Server Home Server MT Base- XDSL XDSL Internet station modem modem UMTS Core Network xDSL Other networks Core network with security and mobility management Figure 15: Long-term vision 3.3.5 Integration of IP and IN networks This section addresses the issue of personal mobility in integrated environments that merge traditional switching and IP based H.323 networks. H.323 is well adapted to integrated working environments, offering multiparty services that support audio- visual components and data sharing, in conjunction with T.120 standards. In order to integrate the two environments, allowing personal mobility interoperation, some evolution needs to be considered in the architecture. Although integration of H.323 with switched networks calls is already addressed by standards, interworking of features such as personal mobility is still unresolved. In this section, the adaptation of IN to a H.323 environment is foreseen in the medium term and a longer-term convergence towards a wider scenario is considered. The starting point for integration of switched to H.323 networks is shown in Figure 16. Interconnecting the two domains is a Gateway (GW) that converts signalling and communication streams in both directions. A Gatekeeper (GK) assures access control and auxiliary functions. GW and GK, if not associated in the same physical device, communicate with each other using IP. Interface between GW and the external signalling world is through ISUP or TUP. IN (opt.) GK FIXED TERMINAL INAP IP MF ISUP IP FT PST N GW H.323 GW - GATEWAY GK - GATEKEEP ER Figure 16: Signalling interfaces in PSTN to H.323 interworking In this configuration personal mobility is limited to a H.323 GK domain area. A local end user is able to use any access point in the network through registration. The GK is able to resolve user aliases transparently to the outside world. © 1999 EURESCOM Participants in Project P809-GI page 19 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 In a first step IN capabilities are added to both ISDN and IP networks, allowing personal mobility through inter-network UPT service provision. A functional architecture is presented in Figure 17. On the IP side, the Gatekeeper is upgraded with IN capabilities, including INAP SCF and SDF functionality. INAP/ IP INAP IN IN GK SCF/SDF ISDN Fixed Terminal H.323 terminal INAP IP DSS1 ISUP IP FT FT N-ISDN GW H.323 GW - Gateway IN GK - Gatekeeper with INAP capabilities Figure 17: Interworking of PSTN and H323 networks with IN support In a next step the core ISDN network is upgraded with IN mobility support, (IN CS-4). This also changes the way in which personal mobility is achieved within the ISDN / H.323 environment. Specific location services in the ISDN environment allow mobility interworking between the ISDN and H.323 environment. The H323 Gatekeeper is updated to interwork with the new INAP mobility management capabilities. HLR HLR / VLR INAP VLR IN IN GK ISDN Fixed Terminal INAP IP DSS1 ISUP IP FT N-ISDN GW H.323 GW - Gateway IN GK - Gatekeeper with INAP capabilities Figure 18: Interworking with Mobile Networks (Cellular) 3.4 Fixed network strategy conclusions For support of broadband multimedia services via the fixed network a number of technologies are available, e.g. B-ISDN and xDSL. The choice of technology may depend on the starting point as these can all provide the required bandwidth. Introduction of IN will enable easy introduction of new multimedia broadband services and together with the fast growth in IP based services will require updates of the access network. An evolution strategy based on stepwise integration of new and existing access networks for business and residential market segments is proposed. Support for mobility will require updates in the core network. Enhanced IN with mobility support may enable service provision to a user via the fixed network from different access points and terminals. Radio access offering the user service access while on the move is the largest challenge to fixed network operators. Some systems are available, but currently the most promising standard for support of future broadband services is UMTS. As the UMTS technology can be applied in the page 20 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility subscriber domain, it will enable fixed network operators to provide multimedia services via radio access and hence offer services similar to those of mobile network operators. For mobile services requiring very high data transfer rates the BRAN technology in combination with UMTS will offer long term solutions useful for fixed network operators. © 1999 EURESCOM Participants in Project P809-GI page 21 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 page 22 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility 4 Evolution Strategy for Mobile Network Operator This chapter identifies the starting point, that is the state of the art technology available for the support of the mobile packet mode services. EDGE, Agents, Wireless Application Protocol (WAP), and the Quality of Service aspects of Internet are presented as enabling technologies of a great importance. UMTS radio access is a self-evident enabling technology, but the access to the UMTS frequency band requires an UMTS licence. The acquisition of the licence is of operation strategic value. The vision of the EURESCOM P809 Project, i.e. the introduction of mobile multimedia services, can be pursued by exploiting the opportunities offered by these key technologies. 4.1 Starting point: GPRS The existing GSM network is globally widespread and it is still growing strongly. Network operators have made large investments to the GSM technology. That is also why the new services should be introduced in such a manner that GSM should not be abandoned for a long time. The GPRS is such a solution. Being the only packet switched mobile communications technology it is a natural starting point for the evolution of the present GSM network structure towards the packet switched mobile network. Adding GPRS functions to existing GSM network creates a network which is capable of transmitting both circuit switched voice calls and packet switched data. The GPRS enhanced radio interface, can transfer bursty packet switched traffic over the radio interface more efficiently than the current GSM radio interface. From the clients' point of view the possibility to pay only for the data actually transferred gives new service possibilities. The permanent on-line connection and the possibility to have single terminal for voice, data and multimedia connections as well as having all used services and their billing grouped together makes the market attractive for masses. Together with the fast and imaginative WWW-based service creation, this brings in new service providers and therefore boosts the quality and variety of mobile services. HLR MAP GSM BSS A PCM ISUP ISUP MSC GMSC N-ISDN BTS BSC VLR Frame IP/ Gb Gn X.25 BTS BSC relay SGSN GGSN X.25 IP IP IP networks Figure 19. GSM/GPRS network 4.1.1 Enabling Technology: EDGE Access To stimulate the market and provide an early multimedia product offering, GSM and GPRS need to be enhanced to allow the support of multimedia services and the transmission of delay sensitive media simultaneously with delay insensitive media. Enhancements such as EDGE may be used to provide higher data transmission speeds © 1999 EURESCOM Participants in Project P809-GI page 23 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 on GPRS. This will help to bridge the gap between GPRS and UMTS transmission bit rates. EDGE is based on Time Division Multiple Access (TDMA) technology, and its data transfer rates are expected to reach 384 kbit/s. EDGE doesn't require a change in the 200kHz channel spacing of GSM and so is totally compatible with existing air interfaces. The spectral efficiency of EDGE should be significantly higher than in GSM. The radio interface should be designed to maximise spectral efficiency. The EDGE could be used in all GSM bands, and it should be possible to mix EDGE and non-EDGE timeslots on the same carrier. The peak service rates may be provided only in a limited coverage area. There will be a mechanism to have a smooth degradation of the service rates for the outer cell areas. The technical parameters for EDGE should allow an evolution for coverage and capacity, as well as provisioning of future 3rd generation services. With EDGE, most of the 3rd generation services can be provided in GSM. GSM community will be utilising EDGE as a cost-effective solution for high data rates whilst using new spectrum for the WCDMA solution. Handset manufactures will need to have terminals that can be used in both systems. 4.1.2 Enabling technology: Multimode terminals When UMTS will be introduced, it will exist in isolated islands/spots in cities. One of the key objectives of third generation systems is that they should aim at providing services anywhere, anytime. This translates into requirements for the third generation terminals to roam freely between different networks and access technologies. UMTS terminals will exist in a world of multiple standards - other members of the IMT2000 family, second-generation standards, and even satellite systems. The multi-system environment will enable operators to offer maximum capacity and coverage to their users by combining UMTS with the other standards. UMTS terminals will therefore need to be multi-mode or multi-band terminals. The implementation of multiple access technologies for a small terminal in a cost- effective manor is technically difficult. Software radios have been presented as a solution to all system differences and this may be true in the long run, but such technologies won’t be mature enough in the beginning of the next century (do we mean 'decade' or ‘century’?). Therefore, we need the conventional multimode/multiband terminal with second and third generation capabilities at least for the first few years of the next decade. (Comment: I think that the life cycle of terminals is so short that some decades of century would be exaggerated) 4.1.3 Enabling Technology: WAP WAP is an easy and fast method to deploy innovative wireless services. The adoption of the WAP technology for the provision of wireless Internet access will benefit network operators, service providers, handset manufacturers and customers. The WAP forum has proposed its solution to the different normative groups; in particular, as regard GSM, it has been inserted into the ETSI MExE standard. The interaction between network operators and their subscribers is based on a visual interface that is appropriate for handheld devices. This user interface (e.g. the micro- browser) provides users with a set of features analogous to those offered by standard web browsers, even if it has been adapted to deal with the obvious limitations of handheld devices (power of the CPUs, amount of memory, display size, etc.). page 24 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility The cost effective standard web technology is used to connect wireless networks to the web. This also allows that the same content can be accessed from both WAP terminals and standard browsers. In addition, information from the subscriber databases in the wireless network (e.g., user location) can be used for service provision. The WAP protocols are optimized for wireless networks, where low bandwidth and high latency are often encountered. WAP ensures data integrity, privacy and denial-of-service protection. The WAP programming model is closely related to the WWW. The overall content is represented by means of a tag-based language called Wireless Markup Language (WML) that is very similar to HTML. As such, many existing HTML development environments can be used for the deployment of WML applications. In addition, the following benefits can be identified: • Choice among open standard vendors. • The WAP services can be accounted and billed similarly to the voice services. • Reasonable priced terminals can be used thanks to the micro-browser-based architecture that saves terminal resources. • The WAP specification introduces new important features, such as voice/data integration and wireless “push” capabilities. • Different air interface technologies, current and future, can easily be used. 4.1.4 Enabling Technology: Intelligent agents The possibility of the usage of Intelligent Agents, both static and mobile, is a subject matter of increasing interest. In the area of Fixed / Mobile telecommunications the usage of Intelligent Agents could produce a number of advantages; few examples are described below: • Information Filtering Agents, can be used to filter out any perceived unwanted information (discarding out of date or duplicate messages, modifying messages to mach the display or transmission capabilities, etc.). • Business Process Management. Obtaining pertinent, consistent and up-to-date information across a large company is a complex and time-consuming process. An Intelligent Agent-based solution, consisting of multiple agents automatically negotiating and co-ordinating the information collection process might be a perfect solution for this kind of task. • Telecommunications Network and Service Management. Agent technology can be used to simplify the very complex network management that results from the growing number of network elements present in the operators’ network. Similarly they become very useful for controlling service provision when the number and variety of (personalised) services increase. • Automated E-commerce. Currently, commerce is almost entirely driven by human interactions; humans decide when to buy goods, how much they are willing to pay, and so on. Some commerce can be automated. 4.1.5 Enabling Technology: Internet QoS As the Internet expands and begins to cater for the increasing demands on it, the question of performance and in particular the quality of service (QoS) becomes an issue. The Internet operates on what is known as the ‘best effort’ principle. The © 1999 EURESCOM Participants in Project P809-GI page 25 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 Internet will do it’s best to deliver packets of information from remote server to desktop. This makes the Internet of today unsuitable for time sensitive applications such as voice and real time video. When IP services are offered commercially the QoS needs to be managed to assure that the customer receives the service he or she has paid for. The current method to manage Quality of Service in Internet is over provision: the network manager provisions the network resources in such a way that there is always enough for the traffic demands. For multimedia services this approach is simply not good enough, and the principle of service discrimination needs to be used. There are two IETF QoS activities aiming to solve the QoS issue: Integrated Services and Differentiated Services [Reference Deliverable 2]. 4.2 Migration paths This chapter presents four evolution scenarios for the provision of mobile broadband IP-services. The state of the art Internet access is shown with a red arrow in each scenario. In the first one the starting point is GSM/GPRS. The evolution shown in this scenario is compatible to the 3GPP UMTS evolution path, but it extends to the provision of broadband local area network type of access (ETSI BRAN). In the rest of the scenarios licence-exempted access components are offered without the UMTS access. First of these scenarios is based on the use of "UMTS alike core network", while the others use an IP based core network. The last scenario utilises the both current and future fixed telecom network infrastructure for the support of the mobile access to IP-based services. These scenarios might be beneficial to the operators that will not get the UMTS licences. 4.2.1 Scenario 1: GSM/GPRS-UMTS-BRAN In GPRS, the services are accessed with the GSM radio interface, and through the GPRS core. HLR MAP GSM BSS A ISUP ISUP MSC GMSC N-ISDN BTS BSC VLR Gs Gr IP/ Gb Gn X.25 BTS BSC SGSN GGSN X.25 IP MT IP networks Core networks with mobility management Fixed networks Figure 20. GSM/GPRS access to IP networks (ca. 100 kbit/s) The introduction of UMTS radio access will allow higher bit rates and lower transmission costs through additional capacity. page 26 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility HLR MAP GSM BSS A ISUP ISUP MSC GMSC N-ISDN BTS BSC VLR Gs Gr IP/ Gb Gn X.25 BTS BSC SGSN GGSN X.25 IP MT IWU IP networks UTRAN BS RNC Iu BS RNC Core networks with mobility management Fixed networks Figure 21. UMTS Phase 1: UTRA access via the GPRS network (few hundred kbit/s) A UMTS core network might be introduced in the phase 2 of UMTS. This will integrate the provision of both connection oriented and packed mode services to one core network. The introduction of the BRAN access will allow up to 20 Mbit/s access in indoor hotspots. HLR MAP GSM BSS A ISUP ISUP MSC GMSC N-ISDN BTS BSC VLR Gr IP/ Gs Gb Gn X.25 BTS BSC SGSN GGSN X.25 UTRAN IP MT BS RNC IWU Iu IP networks BS RNC ATM UMTS CN ATM Iu BRAN Core networks with mobility management Fixed networks Figure 22. UMTS phase 2: UTRA access via the UMTS CN (few hundred kbit/s)) 4.2.2 Scenario 2: Licence-exempt telecom network The UMTS-TDD and the WLANs can operate at the 2 GHz, 2.4 GHz and 5 GHz licence-exempt frequency bands. The use of these access technologies together with standard UMTS core network solutions can be a beneficial solution for the operators that will not get a UMTS license. © 1999 EURESCOM Participants in Project P809-GI page 27 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 HLR UMTS-TDD Iu Iu IP RLAN UMTS CN IP networks MT Iu BRAN ATM ATM Core networks with mobility management Fixed networks Figure 23. Unregulated access (BRAN/TDD-UMTS) via the UMTS core network (up to 20 Mbit/s) 4.2.3 Scenario 3: Licence-exempted access to IP core network In this scenario the UMTS-TDD and WLAN access is used similarly to the scenario 2 above. This time, however, the GSM->GPRS->UMTS approach is abandoned in the core network, and the required functionalities are implemented using IP-protocols. This scenario results in a situation were public mobile service is offered using wireless Intranet alike system. End-to-end security Mobility related security, charging, etc IP routing IP routing IP routing IP end Foreign Home IP end system Agent Agent system UMTS-TDD IP (over ATM/ xDSL/ ethernet , …) RLAN IP IP networks MT BRAN IP subnetwork IP core network with mobility management Figure 24. BRAN access directly to IP based core network (up to 20 Mbit/s). 4.2.4 Scenario 4: Evolution utilising fixed IP-access technologies In this scenario, the essential network components to provide this access are: • Broadband base-station (e.g. UMTS, Bluetooth, DECT, wireless-LAN); • High capacity modem (e.g. xDSL) to carry bearer and signalling over copper line plant; • UMTS core network introduced; page 28 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility • Mobile IP used for mobility (Home Agent and Foreign Agent) Home Server Mobility Server FT LE TE N-ISDN Circuit switched Network ISP Copper line Gateway MT Base- XDSL XDSL Internet station modem modem UMTS Core Network xDSL Core network with mobility management Other networks Figure 25: Long-term vision 4.3 Conclusions Mobile packet data technology is important because packet switching provides a seamless and immediate connection from a mobile PC to the Internet or corporate Intranet allowing all existing and future Internet applications. The success or fall of the mobile multimedia services depends on service providers. The task for the network technology is to provide them the capabilities to offer new innovative services. IP technology offers flexible service creation environment and allows rapid introduction of innovative new multimedia services. The evolution path to third generation systems is often presented as something of a 'big bang', requiring wholesale upgrades in network infrastructure. With the right service strategy and network planning, GSM operators are in an excellent position to capitalise on the high speed wireless Internet market through a staged evolution of their core networks, with the addition of new radio access technologies as they become available. The key step is the UMTS radio access. The acquisition of the UMTS licence is of operational strategic value. One of the essential objectives of third generation systems is that they should aim at providing services anywhere, anytime. This translates into requirements for the third generation terminals to roam freely between networks. When UMTS will be introduced, it will exist in isolated islands/spots in cities. For these reasons it is important to recognise the following: • A GSM customer needs good reasons to change to UMTS, and the UMTS services must offer all that GSM offer. • Many UMTS terminals will be multi-mode or multi-band GSM/GPRS/WCDMA/ TD-CDMA. © 1999 EURESCOM Participants in Project P809-GI page 29 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 • UMTS terminals will exist in a world of multiple standards - both second- generation standards and other members of the IMT2000 family. This will enable operators to offer maximum capacity and coverage to their users by combining UTRA with second and other third generation standards. Software radios have been presented as a solution to all system differences and this may be true in the long run but probably such technologies won’t be mature enough in the beginning of the next decade. Thus, in one way or another we will need the multi- mode/multi-band terminals. Over the Internet, quality of service is not guaranteed. Until now, ISPs have offered mainly a best effort service (first in first out queuing) and all they required was scalability but there is a strong pressure from different businesses to offer a quality of service on the Internet although there is a mismatch between quality of service and packet switching without reservation. In response to this demand, the IETF proposed two approaches, a complicated integrated Services model which can deliver hard QoS guarantees (similar to connection oriented networks) and a simpler Differentiated Services architecture which try to offer different qualities of service without guarantees. page 30 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility Timeframe Capabilities Notes 9.6 kbps service Available today Circuit-switched data Service available from most and fax GSM operators today. 14.4 kbps service Commercially Higher speed circuit- Should work identically to available during switched data and fax 9.6 kbit/ps service only at 1999 higher peed. V.42 bis compression will further increase throughput by about 200%. Direct IP access Available from Circuit-switched Reduces call set-up time and some carriers connection directly to provides a stepping stone to today Internet packet data. Will also be available for high-speed circuit-switched data services. High-speed Commercially High speed rates up to A software-only upgrade for circuit-switched available during 57.2 kbit/s (when using carriers not requiring data service 1999. 4 timeslots, each 14.4 expensive infrastructure. (HSCSD) kbit/s). Operators will need to decide whether to offer this service or GPRS or both. GPRS Commercially High-speed packet data Extremely capable and available within with transmission speeds flexible mobile a year. over 100 kbit/s, with communications. most user devices offering about 56 kbit/s. EDGE Available within High speed packet data Final high-speed data two years which will triple the technology for existing GSM rates available with networks. Will also be used GPRS with IS-136 TDMA networks. Third generation Available within High speed packet data Completely new airlink. cellular two to four years to 2 Mbit/s Table 2: Road map of mobile data services These steps described above do not have to be implemented in the same order as they are described, but they indicate the possibilities of an evolution path towards a Third Generation System. • GPRS: GPRS is a key step, which coupled with multislot GSM data connections and EDGE modulation will deliver high-speed wireless Internet connectivity to GSM users worldwide. Although in its initial form GPRS is a limited solution to stimulate the packet data market and will provide limited 3G capability, it does provide an upgrade path to full 3G capability. Packet data technology is important because packet provides a seamless and immediate connection from a mobile PC to the Internet or corporate intranet allowing all existing Internet applications such as e-mail and Web browsing to operate smoothly without even needing to dial into an Internet service provider. The advantage of a packet-based approach is that GPRS only uses the medium, © 1999 EURESCOM Participants in Project P809-GI page 31 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 in this case the precious radio link, for the duration of time that data is being sent or received. This means that multiple users can share the same radio channel very efficiently. In contrast, with current circuit-switched connections, users have dedicated connections during their entire call, whether or not they are sending data. Many applications have idle periods during a session. With packet data, users will only pay for the amount of data they actually transfer—not for the idle time. In fact, with GPRS, users could be "virtually" connected for hours at a time and only incur modest connect charges • UTRAN: UTRAN will need to interface to the GPRS elements and may need to interface to the circuit switched elements. Modification to the UTRAN should, however, be avoided. • 3rd generation system based on WCDMA: To support instant access to multimedia services, the WCDMA solution will employ a new random access procedure with fast synchronisation to handle 384 kbps packet-data services. This will reduce the time needed to establish connections between mobile users and base stations to a few tenths of a millisecond. In addition, this WCDMA system will provide great flexibility in user data rates. • EDGE: Those operators who either choose not to take a third generation licence, or are unsuccessful in their bids to obtain one, will be able to use EDGE to secure data rates comparable to those offered by third generation. EDGE will offer rates of 384 kbit/s, enabling second generation operators to maintain a competitive position against third generation operators—at least in the first stage of third generation commercialisation. page 32 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility 5 Common Requirements and Conclusions The success or failure of UMTS depends on the service providers. IP technology offers flexible service creation environment and allows rapid introduction of innovative new multimedia services. In one year, all European third generation frequency bands will be licensed to operators. UMTS is the only technology currently mature enough for operator’s investment decision. This means that UMTS is likely to be the only third generation system to be used in Europe. New technologies such as high-speed Digital Subscriber Line (xDSL) allow traffic to be carried across the copper local loop at bitrates corresponding to UMTS data rates. It is important that the new transport mechanism for a target architecture allows efficient integration of all multimedia traffic flows. A common target architecture for fixed and cellular network evolution must be identified to yield a reduction in operational and infrastructure costs. Strategic considerations for the evolution of G-UMTS The term G-UMTS refers to the use of an evolved GSM core network for support of the UMTS Terrestrial Radio Access Network (UTRAN). It was identified as the market priority for standardisation in the European Telecommunication Standards Institute (ETSI) programme advisory committee expert group report on global multimedia mobility [1]. Their recommendations reflect the likelihood that in most cases UMTS will be deployed by operators that are already signatories of the GSM MoU. Technical work for G-UMTS is currently elaborated in a 3 rd Generation Partner Project (3GPP) to be endorsed by the regional standard bodies. Evolutionary considerations are presented below reflecting an operator perspective which assumes that G-UMTS will be specified in a cost-optimal manner to minimise impact on the GSM infrastructure while reusing GSM functionality where advantageous. This is the starting point for the further evolution of the core network towards full multimedia capability. In consideration of traditional circuit-switched GSM, it is noted that many companies have large investments in equipment such as Base Transceiver Stations (BTS), Base Station Controllers (BSC) and Mobile services Switching Centres (MSC). Systems are widely deployed, they are proven, stable and well understood. It is therefore expected that changes to the GSM circuit-switched components due to the introduction of UMTS will be avoided. To stimulate the market with an early multimedia product offering, the GSM MoU anticipates that GPRS will need to be enhanced to allow simultaneous support of delay-sensitive and delay-insensitive multimedia traffic (TG.60[6]). GPRS nodes will continue to be added in the time-scale for UMTS deployment and technologies such as EDGE may be used to provide higher data rates for GPRS, bridging the gap to UMTS. Phase 1 GPRS functionality will be restricted in comparison with UMTS as there will be limited support for reliable continuity of service (cell re-selection will be used rather than handover), the maximum bit rate will be 170kbit/s and only “best effort” services will be supported. By the time UMTS is available, however, there will be limited GPRS deployment with relatively low investment compared to circuit- switched GSM. Upgrades and replacement of GPRS components are likely and will be less destabilising and costly than replacement of circuit-switched GSM components. © 1999 EURESCOM Participants in Project P809-GI page 33 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 The deployment of the UTRAN will be a huge investment and as a consequence it can be expected that any change to the UTRAN after initial roll out will be limited to software updates. Given the time-scales for UMTS Phase 1 deployment, the UTRAN may need to be connected to the GSM Phase 2+ core network GPRS elements to support packet switching services. For this to happen, an interworking function will be required to interface the UTRAN to the SGSN where the SGSN cannot support the interface to the UTRAN (Iu interface). Moreover, until such time as the GPRS elements can support speech, the UTRAN will have to be connected to the MSCs to provide a speech capability of up to 64kbits/s. Again, an interworking function will be needed to obviate any need for modification of the MSCs. Given the initial patchy deployment of UMTS, there will be a need for handover between the UMTS and GSM radio access for both circuit switched and packet switched traffic. With regard to the evolution of G-UMTS, the target 3G architecture will most likely be an integrated transport network capable of supporting multimedia traffic. Consequently, integration of packet switched and circuit switched mobility management can be expected. In view of limited deployment, the GSM MoU notes that GPRS nodes (SGSN & GGSN) can be evolved or replaced as required and that eventually the UMTS core network will support both delay sensitive and insensitive traffic simultaneously in an integrated network (TG.60[6]). It is concluded that for reasons of efficiency it is important that the new transport mechanism for the target architecture allows efficient integration of all GSM, GPRS and UMTS traffic flows. The GSM MoU notes that GPRS is a first step in the deployment of a mobile packet data network that will offer an evolution path to 3 rd Generation capability (TG.60[6]). Strategic considerations for the evolution of I-UMTS The ETSI programme advisory committee expert group in their report on global multimedia mobility [1] indicated that mobile multimedia services should in principle be available through a range of access and core networks. This consideration holds true for UMTS services, which may be accessed through cellular and fixed/cordless access media attached to suitable core networks. From the perspective of UMTS, an important use of the fixed network will be for cordless/fixed terminal support in business and residential environments. Dual-mode handsets, which switch between UMTS terrestrial and cordless access, offer the potential to free-up limited cellular resources by bypassing the UTRAN for stationary users. There may be cost advantages in accessing mobile multimedia services through the fixed network and the Virtual Home Environment (VHE) could unify service provision across access media. In this document, the term I-UMTS is introduced to denote UMTS service support based on an evolved fixed-network. Evolutionary considerations are presented below reflecting an operator perspective which assumes that I-UMTS should be specified in a cost-optimal manner to minimise impact on the ISDN/PSTN infrastructure while reusing ISDN/PSTN exchanges where advantageous. Operators have large investments in equipment for PSTN and narrowband-ISDN; systems are widely deployed, they are proven, stable and well understood. It is therefore expected that changes to these components due to the introduction of UMTS will be avoided. Due to the growth in IP-traffic, PNOs are expected to continue investment in fixed network infrastructure. In some cases, network operators are entering the market as Internet Service Providers (ISP) and IP-telephony is of interest. page 34 (36) © 1999 EURESCOM Participants in Project P809-GI
  • Deliverable 3 Evolution Strategy for Broadband Mobility New technologies such as high-speed Digital Subscriber Line (xDSL) allow traffic to be carried across the copper local loop at bitrates corresponding to UMTS data rates. Potentially, an Iu interface may be supported over the xDSL local loop for UMTS support in business and residential environments. Traffic at the Iu interface will already be groomed into GSM-voice (A-interface) and GPRS (Gb-interface) types which will enable easy separation of these components. To avoid changes to the exchanges supporting PSTN and narrowband-ISDN, an interworking function may be needed for GSM-voice (A-interface) type traffic. GPRS (Gb-interface) type traffic can be directed to an Internet gateway. The target architecture for the evolution of I-UMTS will most likely be an integrated transport network capable of supporting multimedia traffic. Consequently, integration of packet switched and circuit switched mobility management can be expected. For the same reasons as presented for the G-UMTS evolution, it is important that the new transport mechanism for the target architecture allows efficient integration of all multimedia traffic flows, and a common target architecture must be identified for a reduction in operational and infrastructure costs. The design and evaluation of an integrated fixed-mobile network is being address in EURESCOM Project P919. © 1999 EURESCOM Participants in Project P809-GI page 35 (36)
  • Evolution Strategy for Broadband Mobility Deliverable 3 References [1] ETSI GMM, "Global Multimedia mobility, a standardisation framework for multimedia mobility in the information society". ETSI, 1996. [2] ITU-T, "Rec. Q.931 Digital Subscription signalling System N.1 (DSS1) – ISDN User network interface layer 3; Specification for basic call control". [3] ITU-T, "Rec. Q.2931 Broadband Integrated services digital Network (B-ISDN), Digital Subscriber signalling System N.2 (DSS2) – User- network Interface (UNI), Layer 3 specification for basic call / connection control". [4] RFC 2474 Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers. K. Nichols, S. Blake, F. Baker, D. Black. December 1998. [5] RFC 2475 An Architecture for Differentiated Service. S. Blake, D. Black, M. Carlson, E. Davies, Z. Wang, W. Weiss. December 1998. [6] MoU 3GIG TG.60 “Technical Migration of GSM to Third Generation Networks”. [Wang 97] Wang, Z. “User Share Differentiation (USD)-Scalable Bandwidth Allocation for Differentiated Services”, Internet Draft, <draft-wang- diff-serv-usd-00.txt>, November 1997 P809 D2 EURESCOM P809 Deliverable 2 page 36 (36) © 1999 EURESCOM Participants in Project P809-GI