WLAN-GPRS INTEGRATION FORWLAN-GPRS INTEGRATION FORNEXT-GENERATION MOBILE DATNEXT-GENERATION MOBILE DAT

A NETWORKSA NETWORKS

通訊工程所 蔡名岳通訊工程所 蔡名岳692430028692430028

OutlineOutline

1. INTRODUCTION2. INTEGRATED WLAN AND CELLULAR DATA N

ETWORKS3. INTERWORKING ARCHITECTURES4. CURRENT STANDARDIZATION ACTIVITIES5. A TIGHT COUPLING ARCHITECTURE6. A LOOSELY COUPLED ARCHITECTURE7. CONCLUDING REMARKS

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.

2.INTEGRATED WLAN ANDCELLULAR DATA NETWORKS•ROAMING•SESSION MOBILITY•ENHANCED MOBILE APPLICATIONS

2.INTEGRATED WLAN ANDCELLULAR 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.

2.INTEGRATED WLAN ANDCELLULAR DATA NETWORKS

2.INTEGRATED WLAN ANDCELLULAR DATA NETWORKS• ROAMING: ownership/management proble

m• 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.

2.INTEGRATED WLAN ANDCELLULAR 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

2.INTEGRATED WLAN ANDCELLULAR 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.

3.INTERWORKING ARCHITECTURES

• loose coupling and tight coupling

4.CURRENT STANDARDIZATION ACTIVITIES

1. Common billing and customer care2. 3GPP system-based access control and

charging3. Access to 3GPP GPRS-based services4. Service continuity5. Seamless services6. Access to 3GPP

5.A TIGHT COUPLING ARCHITECTURE• Tight coupling architecture provides a novel sol

ution for interworking between 802.11 WLANs and GPRS– Seamless service continuation across WLAN and GPR

S– 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

5. A TIGHT COUPLING ARCHITECTURE

6. A LOOSELY COUPLED ARCHITECTURE• In tight coupling, the WLAN data traffic d

oes not pass through the GPRS core network but goes directly to the operator’s IP network

6. A LOOSELY COUPLED ARCHITECTURE

6. A LOOSELY COUPLED ARCHITECTURE• 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 GP

RS operator over any WLAN access network, regardless of whether the WLAN is owned by a GPRS operator, (U)SIM-based authentication may be used.

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.

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 mob

ility across GPRS and WLAN domains. The MIP framework consists of a MIP client (the MS), a foreign agent (FA), and a home agent(HA).

CONCLUDING REMARKS

CONCLUDING REMARKS

CONCLUDING REMARKS