mipshop – november, 2005 event services and command services for media independent handover...

MIPSHOP – November, 2005

Event Services and Command Services for Media Independent

Handover

Presentation prepared by: Srini Sreemanthula

Presented by: Greg Daley, with some additions

MIPSHOP

IETF 64


IEEE 802.21 Introduction• IEEE 802.21 WG defines media

independent handover (MIH) services that enable handoffs from one link technology to another involving subnet changes

• MIH services aid in handoff based on existing mobility management protocols

• MIH services are classified as 3 types•MIH Information Services•MIH Command Services•MIH Event Services


What MIH provides

• MIH service carry L2 information that is processed locally or carried to some other network node, remotely

• MIH Services enable two facets of inter-technology handover

• Inter-technology Network selection • Handover control


ES/CS Introduction

• Event Services (ES) provide:•indications from one layer or functionality to another about changes in the connectivity state.

•Remote ES convey information from one network node to another

• Command Services (CS) provide:•mechanisms for controlling handovers or functions aiding handovers.

• mechanisms to establish, redirect, or remove state in either the network or mobile node, so that handovers occur smoothly.

•Remote CS convey information from one network node to another


Motivations

• 802.21 functional definitions are to enable two scenarios

•Terminal centric/controlled

•Network centric/controlled


Terminal Controlled Handover• Terminal makes all the decisions of

network selection and initiates HO control

• Can utilizes native L2 signaling or L2/L3 MIH ES/CS and L3 IS services

• Used in operator, enterprise or individual user scenarios


Network Controlled Handover• Network makes decisions of network selection

in coordination with the terminal and initiates HO control

• Assumption is that •network selection is in core network (beyond L2)•HO control resides where MME (common to both accesses) resides (beyond L2)

• This requires that L3 MIH IS, ES and CS services are available

• Important for operator models with multiple access technologies


Motivation Summary• Higher layer MIH ES/CS services provide

architectural flexibility for 802.21 deployment•does not need 802.21 in certain link technologies

• ES/CS are utilized for both network selection and handover control

•Applicable to network entity common to both media types•Not scalable to provision these functions within subnet

• Easier and faster 802.21 adoption in other SDO e.g. 3GPP

• Can coexist or share functions with MIH ES/CS at L2


ES/CS Service Model

OtherSources

MIHF (ES)

MIH (ES)

Other Sources

Remote ESOthertriggers

Link Layer

Link Layer

Othertriggers

LinkIndications

LinkIndications

NetworkNode

NetworkNode

Other layers/

functions

MIHF (CS)

MIH (CS)

Remote CS Commands

MMELink Layer

LinkCommands

Commands

NetworkNode

NetworkNode

• Event Service model

• Command Service Model


Usage ModelsDirect and Proxy models

• Direct model

• Proxy model

MIHFUE MIHFMME

Remote ES/CS

MIHFUE MIHFproxu MIHFRemote ES/CS Remote ES/CS


NW Initiated NW Selection

MAC Layers

Beacon

802.16-AN 802.11-ANMIHFUE

UE

DL-Burst*

Link-Detect

Link-Detect

802.11-AN

Beacon

MME MIHFNW(IS)

MIH-Register-Event.Resp()

Link-Event.Detect(link_info)

Network Operator

Link-Event.Detect(link_info)

MIH-Register-Event.Req()

MIH-Info.Resp

MIH-Info.Req

Unfavorable

Network

FavorableNetwork

=> Selection

UE Discovery and Registration

MIH-Info.Resp

MIH-Info.Req


NW Controlled HO

MIHFUEMobile IP

UE Operator NetworkHA

802.11 NetworkNew-FA802.11-AN

MIH-Remote-Link-Switch.Req(802.11 nwk)

L2-Procedures (Security, Re-association, QoS Neg.)

Link-Event-Up(802.11 nwk)

MIH-Link-Event-Up

FBU

L3-switch.Ind

802.11 MAC

MIH-Remote-Link-Switch.Resp

Release

Mobile-IP SignalingMIH signaling over new link

Legend

MME

Network Selection

Link-Associate

Proxy Rtr Solicitation

Proxy Rtr Advertisement

Mobile IP update procedure over new link


Remote ES/CS Feasibility• Discussion relevant due to:

• Adoba, B., "Architectural Implications of Link Indications draft-iab-link-indications-03.txt", June 2005.

• Explicit signaling required•Intertechnology handover may not result in IP subnet change

• Mitigation of security issues•Trust issues

• Mapping of identifiers•Done at the UE


Explicit Signalling• Command and event signalling

• Implicit signalling possible• when path changes or link-aware routing metrics from access network

• Explicit signaling required• Intertechnology handover may not result in IP subnet change

• May inform devices of mobility management issues which aren’t apparent in the current access net

• Needs safeguards to ensure damping/robustness


Identifier Mappings

• May be possible to make identifier mappings

Appl/Trans/Netw

MIHFES/CS

Link-Layers

Mapping of Local Identifiers

MME

Discovery

Registration

Authentication

Security Association

Media independent host ID

Mobile Node Network


ES/CS Higher Layer Requirements• Work is similar to IS higher layer MIIS for

•Identifying usage scenarios •Provisioning models e.g. proxy and direct•Finalizing ES/CS MIH functionality

•Message sequences, message types, data elements associated with each message

• Other higher layer requirement categories•Transport Layer•Discovery•Registration and Deregistration •Capability negotiation•Security•Reliability and failure recovery

mipshop – november, 2005 event services and command services for media independent handover...

Documents