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Siemens IEEE802.11 User Manual

Page 76

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WLAN-IEEE802.11 Tutorial (Maximilian Riegel), 021018-wlan-tutorial.ppt

Page 76

© Siemens, 2002

PSTN

PLMN access

PLMN core

VLR

HSS

AUC

SGSN

SCPLNP

IN

GGS
N

TDM / ATM / IP

MSCS

MSCS

BTS

BSC

BTS

Node B

Node B

RNC

internet

wlan local access network

WLAN – UMTS Interworking:
Ancient approach: ‘tight coupling’

WLAN as just another radio access technology of UMTS

n

All UMTS services become available over WLAN.
but:

n

PLMN is burdened with high bandwidth WLAN traffic.

n

Wi-Fi does not provide all the functionality needed (QoS, security).