1. WLAN-GPRS INTEGRATION FOR NEXT-GENERATION MOBILE DATA NETWORKS 通訊工程所 蔡名岳 692430028

2. Outline 1. 1. INTRODUCTION 2. 2. INTEGRATED WLAN AND CELLULAR DATA NETWORKS 3. 3. INTERWORKING ARCHITECTURES 4. 4. CURRENT STANDARDIZATION ACTIVITIES 5. 5. A TIGHT COUPLING ARCHITECTURE 6. 6. A LOOSELY COUPLED ARCHITECTURE 7. 7. CONCLUDING REMARKS

3. 1.INTRODUCTION More necessity and less luxury on the ability to communicate 2G -> 2.5G (GPRS) -> 3G Delay of 3G cellular networks  – –offerings with “ 3G-like ” services in efforts to generate new revenue stream in today ’ s environment.

4. 2.INTEGRATED WLAN AND CELLULAR DATA NETWORKS ROAMING SESSION MOBILITY ENHANCED MOBILE APPLICATIONS

5. 2.INTEGRATED WLAN AND CELLULAR DATA NETWORKS Cellular data network provide – –low-speed data service – –over a large coverage area. WLAN provides – –high-speed data service – –over a geographically small area.

6. 2.INTEGRATED WLAN AND CELLULAR DATA NETWORKS

7. ROAMING: ownership/management problem Cellular owned WLAN – –operators are able to enhance their data service capabilities with high-speed data connectivity WISP owned WLAN – –The WISP may partake in revenue sharing with the cellular operator, based on the particular roaming agreements between the two parties.

8. 2.INTEGRATED WLAN AND CELLULAR DATA NETWORKS SESSION MOBILITY – –An evolutionary step from roaming in this integrated environment. – –Session is defined here as a flow of IP packets between the end user and an external entity – –EX:FTP,HTTP

9. 2.INTEGRATED WLAN AND CELLULAR DATA NETWORKS ENHANCED MOBILE APPLICATIONS – –The possibility of cellular customers being connected to two different access networks, a number of enhanced applications can be enabled. – –take advantage of the fact that the end user is always connected through a low-speed cellular network and sometimes connected through a high-speed WLAN. – –EX: a mobile email application that schedules the delivery of large files when the mobile is connected to the WLAN network, and delivers only synopses of emails when the mobile is connected to the GPRS network.

10. 3.INTERWORKING ARCHITECTURES loose coupling and tight coupling

11. 4.CURRENT STANDARDIZATION ACTIVITIES 1. 1. Common billing and customer care 2. 2. 3GPP system-based access control and charging 3. 3. Access to 3GPP GPRS-based services 4. 4. Service continuity 5. 5. Seamless services 6. 6. Access to 3GPP

12. 5.A TIGHT COUPLING ARCHITECTURE Tight coupling architecture provides a novel solution for interworking between 802.11 WLANs and GPRS – –Seamless service continuation across WLAN and GPRS – – Reuse of GPRS AAA. – – Reuse of GPRS infrastructure – – Support of lawful interception for WLAN subscribers – – Increased security – – Common provisioning and customer care – – Access to core GPRS services

13. 5. A TIGHT COUPLING ARCHITECTURE

14. 6. A LOOSELY COUPLED ARCHITECTURE In tight coupling, the WLAN data traffic does not pass through the GPRS core network but goes directly to the operator ’ s IP network

15. 6. A LOOSELY COUPLED ARCHITECTURE

16. AUTHENTICATION An authentication similar to GPRS may occur within the WLAN network, depending on the particular implementation. Where the GPRS operator owns the WLAN – –the operator will reuse SIM-based authentication (within the WLAN environment. – –for a subscriber to access services provided by a GPRS operator over any WLAN access network, regardless of whether the WLAN is owned by a GPRS operator, (U)SIM-based authentication may be used.

17. 6. A LOOSELY COUPLED ARCHITECTURE ENCRYPTION – –A commonly believed weakness of the 802.11 WLAN standard is in its encryption technology. – –Wired Equivalent Privacy (WEP) has been shown to be a relatively inefficient encryption scheme, if used as is as the only form of encryption. – –With the use of EAP, WEP may be enhanced by the use of a unique session key for each user of the WLAN.

18. 6. A LOOSELY COUPLED ARCHITECTURE BILLING – –Integrated billing is achieved via the billing mediator function in the loosely coupled architecture of Fig.8 SESSION MOBILITY – –Mobile IP (MIP) can be used to provide session mobility across GPRS and WLAN domains. The MIP framework consists of a MIP client (the MS), a foreign agent (FA), and a home agent(HA).

19. CONCLUDING REMARKS