SIP-Based Vertical Handoff Between WWANs and WLANs 1 WLAN-UMTS - - PowerPoint PPT Presentation

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Mar 17, 2023 18 likes •131 views

SIP-Based Vertical Handoff Between WWANs and WLANs 1 WLAN-UMTS Interworking Architecture Loosely coupled integration architecture WWANs and WLANs are connected through the Internet, and each is an independent IP wireless access domain.

SLIDE 1

SIP-Based Vertical Handoff Between WWANs and WLANs

SLIDE 2

WLAN-UMTS Interworking Architecture

Loosely coupled integration architecture
WWANs and WLANs are connected through the

Internet, and each is an independent IP wireless access domain.

Tightly coupled integration architecture
WLANs are incorporated into WWANs as part of its

radio access subsystem.

SLIDE 3

SLIDE 4

SIP Terminal Mobility

Pre-call mobility
Re-registers its new IP address with its “home” by

sending a REGISTER message

Mid-call mobility
Sends an INVITE message about the terminal’s new IP

address and updated session parameters

SLIDE 5

WLAN-to-UMTS Vertical Handoff

SLIDE 6

UMTS-to-WLAN Vertical Handoff

SLIDE 7

Analysis of Handoff Delay

There are two types of delays associated with the

handoff process

Wireless component delay: the delay introduced by the

error-prone wireless links in the UMTS and WLAN access networks for the correct transmission of the associated handoff messages

Processing delay: the queueing delay due to the load in

the computing entities, such as the CSCF servers, SIP servers, and even the mobile host in the signaling path

SLIDE 8

Analysis of Handoff Delay

Let the handoff delay during mid-call terminal

mobility be DHandoff , which can be divided into

The delay during the attachment procedures
The delay due to location update using the SIP INVITE

message.

For handoff to UMTS networks,
For handoff to WLAN

SLIDE 9

Analysis of Handoff Delay

DSIP-UMTS and DSIP-WLAN are the transmission delays
f SIP location update

SLIDE 10

Analysis of Handoff Delay

SLIDE 11