December 2000 European Institute for Research and Strategic Studies in Telecommunications GmbH AT THE THEATRE: Remove the Theatre Bookmark from her homepage PDA ONLINE THEATRE-TICKETS BOOKING Project P920 Realising the Virtual Home Environment (VHE) concept in ALL-IP UMTS networks AT HOME: Add the Theatres Bookmark in her homepage Laptop ON THE WAY HOME: Order Theatre-tickets Mobile phone AT THE OFFICE: Open and browse the Theatres Bookmark Office PC
Goals Virtual Home Environment, All-IP Networks and UMTS This brochure presents some of the results of the EURESCOM project P920 UMTS Network Aspects. The main goal of this project was to undertake an analysis of the technical and user related aspects of Virtual Home Environment (VHE), and to study the provision of VHE services over 3 rd generation networks. For this purpose, a comprehensive VHE trial was designed, implemented and evaluated. These results and further recommendations on a VHE-enabled All-IP implementation of the Universal Mobile Telecommunications System (UMTS) are presented. Virtual Home Environment (VHE) is defined as an environment that enables the user to receive customized and personalized services, regardless of location, access network or terminal type. VHE is based on standardized service capabilities that are consistently presented, allowing the user to always have a common look and feel of the service as well as the same service experience, irrespectively of the access network or the kind of terminal he uses each time. This way the user will not see a difference in using his services while roaming in other networks. The cover page figure demonstrates this: It presents one user accessing her service from various kinds of terminals (laptop, PC, mobile phone) and through various networks (which she even might not be aware of). Modifications to her service profile made with one terminal will of course be valid on all terminals she is using, and in all networks. VHE is an important feature of UMTS. In the perspective of VHE, the All-IP network architecture is proposed as a highly flexible and scalable UMTS core network, providing multimedia and real-/non-real time services. Benefits of VHE VHE provides users with the ability to receive customized and personalized services with a common look and feel, wherever and on whatever kind of terminal. VHE offers the network operators the flexibility to develop customized services across different networks (e.g. cordless, cellular or satellite networks), without requiring modifications of the underlying network infrastructure. VHE offers the service providers a set of components for flexible service creation, enabling them to develop services whose appearance adapts to the network and terminal capabilities. Services E-mail WWW/WAP Audio/Video Speech Terminals Access GSM access UTRAN LAN WLAN Analog Digital Core Network GSM GPRS UMTS IP PSTN Uniform service presentation over different networks and terminals UTRAN: UMTS Radio Access Network WLAN: Wireless LAN WAP: Wireless Application Protocol PSTN: Public Switched Telephone Network GPRS: General Packet Radio Service 2
Call, Service and Mobility Control for support of VHE in UMTS All-IP reference model The need for a global support of VHE throughout the various IP architectures currently being studied in different forums (e.g. 3GPP, IETF, ITU, TIPHON) led to the proposal of a generic model for an All-IP core network architecture. This model is a general functional abstraction for providing VHE services in an All-IP network and can be mapped to all different architectures studied by forums. Call Agent: Performs call control and service logic triggering. User Profile/Location Servers: Store user s preferences for his or her services and user s location, respectively. Trunking Gateway: Performing media conversion and signaling adaptation for the interworking of different networks. Service Capability Features: Storage of service logic (e.g. could be the SCP (Service Control Point) of IN). UMTS Call Control Alternatives: H.323, Session Initiation Protocol (SIP) SIP was identified as a preferable solution for call control, as compared to H.323, in terms of complexity, extensibility and scalability. However, it was identified that the basic SIP protocol has to be enhanced in order to meet the requirements for call-, service control and mobility management in a VHE environment. The Distributed Call Signalling (DCS) and Media Gateway Control (MEGACO) architectures from IETF were identified as possible attractive alternatives for an All-IP core network. Project results provide a mapping of these functional architectures to the P920 All-IP reference model, setting up an interesting base for comparison. Services & Applications Service Management Application Interface Network Capability Interface User Location Server Local info Register Call Agent User Profile Server IP Backbone Service Capability Features Call Agent Mobility Management Service Control Call & Session Control Network Resource Protocols Wireless Access Trunking Gateway Router Trunking Gateway Wireline Access Transport IP Access Generic Model for All-IP core network architecture 3
VHE Application OSA Interface Framework (Authentication and Discovery) SCS (Service Capability Server) SCS (Service Capability Server) Nonstandardised interface HLR (Home Location Register) CSE (CAMEL Service Environment)... CSCF (H.323 Gatekeeper/SIP Server) VHE application invocation based on OSA UMTS Service Control for VHE VHE service control can be based on the Open Service Architecture (OSA). OSA is an architecture, enabling applications to make use of network capabilities via standardised interfaces (namely OSA interfaces). They are defined between the applications and the Service Capability Servers (SCSs). Service Capability Servers provide abstractions of the underlying network functionalities. This way, applications become independent from the network technology. In terms of network signalling for service control, it was identified that in All-IP networks IP-based signalling will be eventually used. Nevertheless, for compatibility reasons, existing IN services should still be supported in 3G networks. H.323, SIP, DCS and MEGACO have been considered and are proven capable of triggering IN services. To enable the triggering of VHE services based on mobility event detection, the Basic Mobility State Model (BMSM) was defined. UMTS Mobility Control Mobile IP has been considered as a possible option for mobility control in UMTS. Mobile IP and its optimization schemes (including those for micro mobility) have been examined in the VHE framework and the need for further study on their adaptation to VHE was identified. 4
VHE Trial Trial Architecture For the trial, two WLAN networks and a UMTS Terrestrial Radio Access Network (UTRAN) were connected to the Internet. The VHE concept is implemented for the trial with the aid of a Media Gateway and a VHE server, both connected to the Internet. Mobility Agent VHE User 1 Mobility Agent Trial Key Components The VHE Server is used in the trial in conjunction with the MGW for customised and personalised service delivery to the user. VHE Server: The VHE server is a basic implementation of the UMTS VHE concept and is based upon a central database which stores information about: The networks attached to the system. The customers using the VHE and their preferences. Media Gateway: The Media Gateway is used as a means for inter-working between classical telephony and data services and also as a means for universal service access from a variety of end user systems (fixed or mobile), by performing media conversion and adaptation. In the trial, the Media Gateway performs the Unified Messaging System, which is one form of the concept of the unified service delivery to the user. Trial Scenarios The trial successfully tested the following scenarios: 1. A WLAN user logs himself on the VHE server and receives voice calls, news (nonreal-time) and streaming video (real-time). 2. The WLAN user roams to the other WLAN sub-network with successful handover for each of the services. 3. A user accesses the VHE server through UTRAN, again receiving news and streaming video. 4. A videoconference is set up between a WLAN and a UTRAN user. UTRAN Access Network VHE Trial architecture WLAN Access Network VHE User 2 Media Gateway VHE Server Trial Results Successful access to the VHE server from both WLAN and UTRAN and successful retrieval of services. WLAN Roaming for all services: The connection is still active and a handover notification is displayed on the VHE user's laptop screen. In addition, the user is notified that services and content will be adapted to the nature of the roaming network. Service and content adaptation: Depending on the type of user s terminal and the user s access network, service adaptation is performed either through media conversion or through mobility management. Videoconference: Using NetMeeting a successful videoconference was conducted. Internet Common Control Network 5
A long-term vision of an All-IP UMTS network The evolution towards an IP-based architecture is proposed for both fixed and mobile telecommunication networks. 2G cellular networks already provide data services and 3G networks are designed to provide wireless Internet connectivity. 2G systems (GSM) deal with mobility at the link layer using proprietary protocols. 3G systems (UMTS) deploy Mobile IP in the core network, yet use proprietary link layer protocols for mobility in the access network. The next generation of wireless networks will probably utilise IP devices only. Hence, the shift towards using IP based protocols only is gradually gaining ground. IP stack adaptation for Wireless Environment needs In future wireless networks real-time and nonreal-time traffic will be transported over the IP protocol. However, the IP protocol stack (being fixed network oriented) is not customized to the specific needs of the wireless medium. There need to be Quality of Service (QoS) guarantees for real-time applications, adaptation to the error-prone, and low-bandwidth wireless medium, and inherent security in the communications. IPv6 will be the answer to some of those requirements. Further enhancements to the IP protocol stack are necessary, though, in order to deal with the wireless medium peculiarities. HAWAII (Handoff Aware Wireless Access Internet Infrastructure) MIP (Mobile IP) IP TeleMIP (Telecommunication Enhanced Mobile IP) Mobility in future All-IP networks Mobile IP is the current standard for supporting macro-mobility in IP networks and is mainly targeted to provide connectivity for a small number of nodes roaming from one fixed network to another. IP based protocols like - Cellular IP, HAWAII, EMA and TeleMIP are the mobility protocols adequate for future All-IP mobile networks dealing with micro-mobility. However, as a medium-term solution, an architecture may be considered where existing Mobile IP and WLAN protocols form a two level hierarchy. EMA (Edge Mobility Architecture) Mobility protocols for future mobile networks CIP (Cellular IP) Introduction of standard IP routers in UMTS The motivation behind introducing standard IP routers in the UMTS network is very clear. By using standard IP routers, operators could save a significant amount in their network investments, since they can reuse their infrastructure. However, using standard IP routers in UMTS sets various requirements to the network architecture, as well as to the routers themselves. Conclusion The project results give substantial proof of the technical viability of the Virtual Home Environment concept and provide information for the specification of UMTS beyond release 00. The VHE trial recommends desirable enhancements to the VHE concept for implementation in a quasi-operational environment. The full project reports are available at: http://www.eurescom.de/ public/projects/p900-series/ p920/p920.htm 6
Publications resulting from this work: 1. "The Virtual Home Environment Architectures and Trials, Geoff Richman and Antonella Napolitano, IST Mobile Summit, 1-4 October 2000, Galway, Ireland 2. "VHE Trial over Mobile IP, Lionel Morand, Jean-Claude Samou and Serge Tessier, IEEE workshop on Service Portability at Globecom 2000, 1 December 2000, San Francisco, USA The Project Participants: Project Leader: Geoffrey Richman BT geoff.richman@btinternet.com Timo Sippola Finnet Group timo.sippola@elisa.fi Maria-Amparo Sanmateu Deutsche Telekom AG amparo.sanmateu@telekom.de Jean-Claude Samou France Télécom jeanclaude.samou@rd.francetelecom.fr About Eurescom project P920 EURESCOM Project P920 "UMTS Network Aspects started on 16 February 1999 and ended in December 2000. The project was led by Mr. Geoff Richman (BT). Additional information can be obtained from: http://www.eurescom.de/ public/projects/p900-series/ p920/p920.htm Emmanuel C. Tzanettis emmanuel.tzanettis@oteresearch.gr Giuseppe Geuna giuseppe.geuna@cselt.it Raquel García-Pérez rgp@tid.es Tor Jansen tor-magnus.jansen@telenor.com OTE Telecom Italia Telefónica I+D Telenor AS Project Supervisor: Uwe Herzog herzog@eurescom.de EURESCOM GmbH 7
European Institute for Research and Strategic Studies in Telecommunications GmbH Schloss-Wolfsbrunnenweg 35 69118 Heidelberg, Germany Tel.: +49 6221 989-0 Fax: +49 6221 989 209 E-mail: info@eurescom.de http://www.eurescom.de EURESCOM is the leading institute for collaborative R & D in telecommunications. We work as a virtual company using the resources of our shareholders to perform highimpact research projects. Our shareholders are major European network operators and service providers. Any network operator and service provider may join EURESCOM as a shareholder. Our focus is on Europe, but we are open to companies from other regions of the world. Other telecommunication industry players, like equipment manufacturers and software vendors, may become members of EURESCOM.