Transcript 投影片 1

A Cross-Layering Design for IPv6
Fast Handover Support in an
IEEE 802.16e Wireless MAN
Youn-Hee Han, Heejin Jang, JinHyeock Choi,
Byungjoo Park and Janise McNair
IEEE Network, 2007
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Outline
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Introduction
IEEE 802.16e WMAN Deployment
Architecture and Handover Procedures
Fast Handover for Mobile IPv6 (FMIPv6)
Cross-layering Design for FMIPv6 over
IEEE 802.16e
Main Factors of Handover Latency
Concluding Remarks
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Introduction
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IEEE 802.16e standard adds mobility
support to the original standard.
Handover is the process of maintaining
the active sessions of a mobile terminal
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When terminal(MS) changes its point of
attachment to the access network.
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Introduction
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(cont’)
There are two types of handovers for the
IEEE 82.16e network environment
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Link layer handover
Reside in the same IP subnet.
 The terminal need only re-establish a link layer
connection without changing its IP configuration.
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IP layer handover
Reside in different IP subnet or in different
networks.
 Must establish new link layer connection and new
IP configuration.
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IP Layer Handover
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IP layer handover for mobile terminal is handled
by mobile IPv6(MIPv6).
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Doesn’t solve the handover latency problem for IEEE
802.16e.
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With IPv6 alone, three main procedure will result
in large delay:
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It acts as a location and routing-path management protocol.
Movement detection
Address configuration and confirmation
Location registration and return routability
Fast MIPv6 was design to reduce or eliminate
packet loss and handover delay in MIPv6.
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IEEE 802.16e Deployment
Architecture
Centralize Control
the subnet
Support only PHY and
link layer functionality
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IEEE 802.16e Deployment
Architecture
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IEEE 802.16e Handover Procedure
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FMIPv6
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The primary goal of FMIPv6 is to eliminate
the delay on IPv6
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Movement detection
Address configuration
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FMIPv6 enable a terminal to quickly detect when it
is moving to a new subnet.
Two different mode
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Predictive fast handover
Reactive fast handover
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Predictive Mode
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Predictive Flowchart
Handover Initiation
If terminal found new Access point,
terminal
Handover
Acknowledgement
will send Router Solicitation for Proxy Advertisement
Because
get
prefix current
information
of new
network,
to accessterminal
router, to
request
access
router
terminal
create
new Care
Address,
and
send the can
prefix
information
of of
access
router
bysend
Proxythe
Router
Information
to current access router by fast binding update.
Advertisement.
Fast Neighbor Advertisement
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Reactive Flowchart
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Add FMIPv6
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If the terminal moves to a different subnet
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Re-configure a new IP address
Re-establish its IP connection
The terminal must conduct a network
layer mobility mechanism.
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To resume the active session after link layer
handover procedure.
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Cross-Layering Design
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Trigger IP layer module.
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Cross-Layering Design
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Handover Initiation.
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Cross-Layering Design
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Handover Execution.
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Cross-Layering Design
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Handover Completion
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Handover Latency
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MAC layer delay: the time from MOB_HOIND to network re-entry complete.
D1: the time from terminal receiving FBAck
to sending MOB_HO-IND message.
D2: the time from receiving LINK_UP event
until sending FNA message.
D3: the time from sending FNA message
until receiving the first packet from the
target AR.
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Handover Latency
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D4: the time from sending FNA message
until receiving the first packet from target
AR.
Predictive mode:
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MAC layer delay+D1+D2+D3
Reactive mode:
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MAC layer delay+D2+D4
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Concluding Remarks
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Presented two handover protocols for IP
layer and MAC layer used in mobile
network.
Created a cross-layer design to enable
proper FMIPv6 with the IEEE 802.16e
handover process.
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Provided three events and one command for
supporting interaction between IP layer and
MAC layer handover procedure.
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