Transcript PPT_692410078

WLAN-GPRS Integration For
Next-Generation Mobile Data
Networks
Wireless Communications
IEEE 2002
報告者：陳崇凱
Authors
 Apostolis K. Salkintzis, Motorola
 Chad Fors, Motorola
 Rajesh Pazhyannur, Motorola
Outline
 Integrated WLAN and cellular data networks
 Interworking architecture
 Current standardization activities
 A tight coupling architecture
 A loosely coupled architecture
 Conclusion
Integrated WLAN and Cellular Data
Networks
Roaming
Between WLANs and cellular system
Session mobility
Session : a flow of IP packets between the end
user and an external entity
Enhanced mobile applications
Ex : mobile email application
Interworking Architecture
Loose coupling and Tight coupling.
With loose coupling the WLAN bypasses
the GPRS network and provides direct
data access to the external packet data
networks (PDNs).
With tight coupling the WLAN data traffic
goes through the GPRS core network
before reaching the external PDNs.
Current Standardization Activities
 Scenario 1 — Common billing and customer
care
 Scenario 2 — 3GPP system-based access
control and charging
 Scenario 3 — Access to 3GPP GPRS-based
services
 Scenario 4 — Service continuity
 Scenario 5 — Seamless services
 Scenario 6 — Access to 3GPP circuit-switched
services
A Tight Coupling Architecture
Providing a novel solution for interworking
between 802.11 WLANs and GPRS.
System description
Protocol architecture
WLAN adaptation function
GIF/RAI discovery procedure
A Tight Coupling Architecture
 BENEFITS
Seamless service continuation across WLAN and GPRS.
Reuse of GPRS AAA.
Reuse of GPRS infrastructure and protection of cellular
operator’s investment.
Support of lawful interception for WLAN subscribers.
Increased security.
Common provisioning and customer care.
Access to core GPRS services
A Loosely Coupled Architecture
authentication
encryption
billing
session mobility
Conclusion
The recent evolution and successful
deployment of WLAN systems worldwide
has fueled the need for interworking
mechanisms between WLANs and cellular
data networks such as GPRS.
Comparison : tight coupling vs. loose
coupling