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IEEE 802.21 MEDIA INDEPENDENT HANDOVER DCN: 21-10-0114-03-srhoTitle: Comments and Questions for Optimized Single Radio

Handover Procedures of WMFDate Submitted: July 13, 2010Presented at IEEE 802.21Authors or Source(s):Yoon-Young An, Junghoon Jee, Hongseok Jeon, Changmin Park, Byungjun Ahn

(ETRI)

Abstract: Comments and Questions for Optimized Single Radio Handover Procedures of WMF

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IEEE 802.21 presentation release statementsThis document has been prepared to assist the IEEE 802.21 Working Group. It is

offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.

The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802.21.

The contributor is familiar with IEEE patent policy, as outlined in Section 6.3 of the IEEE-SA Standards Board Operations Manual <http://standards.ieee.org/guides/opman/sect6.html#6.3> and in Understanding Patent Issues During IEEE Standards Development http://standards.ieee.org/board/pat/guide.html> 

IEEE 802.21 presentation release statementsThis document has been prepared to assist the IEEE 802.21 Working Group. It is

offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.

The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802.21.

The contributor is familiar with IEEE patent policy, as stated in Section 6 of the IEEE-SA Standards Board bylaws <http://standards.ieee.org/guides/bylaws/sect6-7.html#6> and in Understanding Patent Issues During IEEE Standards Development http://standards.ieee.org/board/pat/faq.pdf> 

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Optimized Single Radio Handover Key Features

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Pre-Registration over L3 tunnel• E.g., WiMAX SFF (Signaling Forwarding Function) performs target BS (Base

Station) operations while the MS is located in non-WiMAX Access network• MAC messages transfer over L3 tunnel• Pre-registration toward target WiMAX network

BS(Target)

Serving AP

ASN-GW (MAG)

IP Core Network

AR/MAG

BS(Another Candidate)

WiMAX SFF

HA/LMA

Data

Pre-registration through L3 tunnel

ASN-GW (MAG)

HO Preparation

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Review of Detailed Procedures - WiMAX IWK case

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Overall Steps

MS WiMAXSFF BS ASN-GW AAA HA

IP CoreNetwork

Phase 2: SR Handover Session Pre-Pregistration Phase

Phase 3: SR Handover Action Phase (Pseudo Activeà Active or Pseudo Activeà Pseudo Idleà Active )

Phase 4. SR Handover Resource Revocation Phase

Phase 1: SR Target Network Detection and SFF Discovery Phase

DNS

Note: Figure from DCN 21-10-0068-00-0000 and clarification is marked as blueNote: Figure from DCN 21-10-0068-00-0000 and clarification is marked as blue

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Phase-1: SR Target Network Detection and WiMAX SFF Discovery

MS/AT SourceSystem

LocalDHCP AAA

3. DNS Query

4. DNS Answer (SFFs IP address)

1. Domain Name acquisition via DHCP

SFFInformation

ServerDNS

2. Generate FQDN for SFF discovery

802.21 Information Service Query and Response

Note: Figure from DCN 21-10-0068-00-0000 and Note: Figure from DCN 21-10-0068-00-0000 and the Information Service query is added by referencing DCN 21-10-0005-00-0000the Information Service query is added by referencing DCN 21-10-0005-00-0000

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Assumption for Phase 2&3• In case of SRHO from WiFi to WiMAX networks• Pre-registered ASN-GW includes Authenticator• Target ASN-GW is different from the pre-registered ASN• Apply CSN Anchored Mobility

• IP mobility protocol PMIP

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IKEv2 procedure to setup a secure tunnel

Phase-2: SR Handover Session Pre-Registration (1)

Phase2

MS_Attachment_Req

MS_Attachment_Ack

1. Initial Network Entry Procedure (stage3 4.5.1.1)

MS-to-Network EAP

authenticationProcess

+ IEEE 802.16eregistration

Data

DCD/UCD & BSID

Connections Establishment

MS-to-Network EAP authentication process

MS_Attachment_Rsp

WiMAXSFF

MS

WiMAX

Target ASN-GW (MAG)

LMA/HA AAA

AP/AR (MAG

)WiFi

Pre-registered ASN-

GW(MAG) /Authenticator

IP Core Networ

k

Information Server

Target BS

secure tunnel

REG_REQ

REG_RSP

Data Path Establishment

RA(with HNP)

IP Address Configuration for WiMAX Interface

AAA query with MS ID

AAA reply with profile(HNP)

WIMAX SFF starts to perform BS operation

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Phase-2: MS-initiated SRHO Preparation (2)

2. Active mode HO Preparation Procedure

• Successful

HO Preparation Phase (stage3 4.7.2.1.2) Context retrieve

DP Pre-Reg.

HO_RspMOB_BSHO_Rsp

• Successful HO Action Phase (stage3 4.7.2.2.2)

HO_Ack

MOB_MSHO_IndHO_Cnf

HO_Cnf

HO_Ack

MS

WiMAXWiFi

HO_Req

WiMAXSFF

Target ASN-GW (MAG) LMA AAA

Pre-registered ASN-

GW(MAG) /Authenticator

Information Server

MOB_MSHO_Req

HO_Ack

This message includes one or more potential target BS’s

This message initiates a handover to one of the target BSs

AP/AR (MAG

)

Target BSTarget

BS

HO_Rsp

HO_Req

HO_Ack

IP Core Network

Data

Information Server query and response

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Phase-2: Network-initiated SRHO Preparation (2)

2. Active mode HO Preparation Procedure

• Successful

HO Preparation Phase (stage3 4.7.2.1.2) Context retrieve

DP Pre-Reg.

HO_RspMOB_BSHO_REQ

• Successful HO Action Phase (stage3 4.7.2.2.2)

HO_Ack

MOB_MSHO_IndHO_Cnf

HO_Cnf

HO_Ack

MS

WiMAXWiFi

HO_Req

WiMAXSFF

Target ASN-GW (MAG) LMA AAA

Pre-registered ASN-

GW(MAG) /Authenticator

Information Server

HO_Ack

This message initiates a handover to one of the target BSs

AP/AR (MAG

)

This message includes one or more potential target BS’s

IP Core Network

Pseudo Active Timer Expire

Information Server query and response

Target BSTarget

BS

Data

HO_Req

HO_Rsp

HO_Ack

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Comments for Phase 2• During Active Mode HO Preparation procedure, suddenly WiFi

link is disconnected.• WiMAX interface of MS will perform the normal

attachment procedure.• We have to consider the reactive mode process.

12

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Phase-3: SR Handover Action

Network ReEntry

PBU

PBA

Data

• Successful HO Action Phase (stage3 4.8.5.5)

Current State Active State

MS

WiMAXWiFiWiMAX

SFF

Target ASN-GW (MAG) LMA AAAInformation

ServerTarget

BS

Pre-registered ASN-

GW(MAG) /Authenticator

Anchor_DPF_HO_Trigger

Anchor_DPF_HO_Req

Anchor_DPF_Relocate_Req

Anchor_DPF_Relocate_Rsp

Access-Request/MAR

Access-Accept/MAA

Anchor_DPF_HO_Rsp

Anchor_DPF_Relocate_Ack

Context_Rpt(Anchor ASN GW ID)

Context_Ack

AP/AR (MAG)

HO Latency in SRHO

Bi-Dir tunnel

IP Core Network

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Comments for Phase 3

• WiMAX forum applied ASN anchored mobility(state 3 4.7) to single radio inter-RAT HO procedures

• Inter-RAT HO needs IP mobility(MIP, PMIP).• CSN anchored mobility has IP mobility function.