high mobility 를 지원하는 ipv6 기술 : ipv6 over wibro internet computing laboratory @ kut ()...

High Mobility 를 지원하는 IPv6 기술 : IPv6 over WiBro

Internet Computing Laboratory @ KUT(http://icl.kut.ac.kr)

Youn-Hee Han(Chair of TTA PG302 WiBro6 WG)

IPv6 and Mobility over WiBro2 [2007 차량 통신 기술 워크샵 ]

Table of Contents

IPv6 over WiBro WiBro and IPv6 – Network Architecture Technical Issues Standardization Trends

Network-based Mobility Why? Proxy Mobile IPv6 Overview

Conclusions


IPv6 Link over WiBro Network Architecture

IPv6 & Network Model in WiBro/IEEE 802.16

IP NetworkIP NetworkInternetInternet

E R E R

ACR

L2 Switch

RAS

MS

DHCP

AAA

ACR ACR

DNSNMS

IP NetworkIP NetworkInternetInternet

E R E R

ACR

L2 Switch

RAS

MS

DHCP

AAA

ACRACR ACRACR

DNSNMS

IPv6 Protocol

Suite(Neighbor)

PSS


WiBro Network Architecture

PSS 1

PSS 2

PSS 3

PSS 4

PSS 5

PSS 6

RAS 1

RAS 2

RAS 3

ACR 1

ACR 2

Point-to-multipoint (PMP)Components

PSS: Portable Subscriber Station RAS: Radio Access Station (Omniscient) ACR: Access Control

Router Knows about all PSSs and RASs

attached to itself Only one ACR at any PSS and RAS

A transport connection always exists between PSS and ACR

PSS – RAS: IEEE 802.16 MAC connection Connection ID

RAS – ACR: GRE Tunnel Traffic is delivered all the way to ACR by

using GRE tunnel between RAS and ACR


IPv6 Link over WiBro Network Architecture

PSS 1

PSS 2

PSS 3

PSS 4

PSS 5

PSS 6

RAS 1

RAS 2

RAS 3

ACR 1

ACR 2

IP Link An ACR Multiple RASs attached to the ACR Multiple PSSs attached to these

RASs

ACR is the first hop access router of a PSS.

Even from IP perspective, an PSS cannot communicate with another PSS directly.

All traffic go through an AR. It implies that an PSS's on-link

neighbor is only an AR.

IP Link 1

IP Link 2


Subnet Model Determination

Service SpecificConvergence Sublayer

(CS)

MAC Common Part Sublayer(MAC CPS)

Privacy Sublayer

Physical Layer(PHY)

PHY SAP

MAC SAP

CS SAP

MAC

PHY

1) Transformation or mapping of external network data1) Transformation or mapping of external network data2) Classifying external network SDUs and associating them 2) Classifying external network SDUs and associating them to the proper MAC service flow and Connection IDto the proper MAC service flow and Connection ID

P1

P2

P3

Packet Classifier

P1 P2 P3 P4 P5

CID 1 CID 2 CID 3 CID 4 CID 5

Source IP Address

Destination IP Address

Source Port Destination Port

PROTO

Connection ID

Packet Classifier

HLver TOS Length

ID 3F 13Flag Offset

TTL HCSPROTO


Source IP Address

0 31

IP

Destination PortSource Port

Length CheckSum

UD

P

UDP / IP

Destination PortSource Port

TC

P

Sequence Number

Rcv Win SizeHL

CheckSum

Acknowledgement Number

Prt Urgent Data

reserved U A P R S F

HLver TOS Length

ID 3F 13Flag Offset

TTL HCSPROTO


Source IP Address

0 31

IP

TCP / IP

P4

P5

IPv4 Packet Mapping

IPv6Packet header

How to efficiently map ?

Convergence Layer & IPv6 Packet Transport



IEEE 802.16 LinkIEEE 802.16 Link

IPv6 Link (Subnet)IPv6 Link (Subnet)

PSS1PSS1

BSBS(RAS)(RAS)

ARAR(ACR)(ACR)

PSS3PSS3

PSS2PSS2

From the viewpoint of IPv6 ND, BS is just link-level bridge. Unlike IEEE 802.11, however, From the viewpoint of IPv6 ND, BS is just link-level bridge. Unlike IEEE 802.11, however, IEEE 802.16 BS is always acting as the termination point for a communication IEEE 802.16 BS is always acting as the termination point for a communication by using by using Connection IDConnection ID instead of MAC address instead of MAC address

IEEE 802.11 MAC HeaderIEEE 802.11 MAC HeaderFrameControl

DurationID

Addr 1 Addr 2 Addr 3 Addr 4SequenceControl

2 2 6 6 6 62

802.11 MAC Header

Bytes:

Recipient Recipient Addr.Addr.

Transmitter Transmitter Addr.Addr.

802.16 MAC Header

FromDS: Original Source Addr., ToDS: Final FromDS: Original Source Addr., ToDS: Final Destination Addr.Destination Addr.

Special Special Addr.Addr.

IEEE 802.16 Link vs. IPv6 Link (Subnet)



PSS 1PSS 1

BSBS(RAS)(RAS)

ARAR(ACR)(ACR)

PSS 3PSS 3

PSS 2PSS 2

Ethernet HeaderEthernet Header(Source MAC, (Source MAC,

Destination MAC)Destination MAC)

IPv6 HeaderIPv6 Header(Source IP, Destination (Source IP, Destination

IP)IP)




IP)IP)

PSS 1PSS 1

BSBS(RAS)(RAS)

ARAR(ACR)(ACR)

PSS 3PSS 3

PSS 2PSS 2


IP)IP)


IP)IP)

GRE HeaderGRE Header

DATA PayloadDATA Payload




IP)IP)DATA PayloadDATA Payload

Ethernet CS/BridgingEthernet CS/Bridging IP CS/GRE TunnelIP CS/GRE Tunnel




Subnet Model DeterminationIPv6 subnet models

Shared Prefix Model One (or more) prefixes advertised on the link No native on-link multicast is possible with this method.

However ACR can implement proxy mechanism All PSSs send the packets to ACR irrespective of the

destination link local scope packets are relayed by ACR

IP CS WiMAX has chosen it.

But, doesn’t decide yet.

[draft-madanapalli-16ng-subnet-model-analysis-00.txt, Sept. 6, 2006]

L3

L2

PSS 1

RAS

ACRWireless Peer-to-Peer Connection

GRE Tunnel

IPv6 (Shared Prefix Model)

L2 RAS GRE Tunnel

L3

PSS 2

IPv6 (Shared Prefix Model)


Subnet Model DeterminationIPv6 subnet models

Unique Prefix Model the unique prefix per PSS Only an ACR and a PSS belong to an IPv6 link. Many IPv6 functionalities can be implemented without

difficulty. If PPP is used between PSS and ACR, most look

straightforward.But, PPP CS is not available yet.

DAD might be needless Suitable to Cellular-like modelL3

L2

PSS 1

RAS

ACRWireless Peer-to-Peer Connection

GRE Tunnel

IPv6 (Unique Prefix Model)

L2 RAS GRE Tunnel

L3

PSS 2

IPv6 (Unique Prefix Model)

[draft-madanapalli-16ng-subnet-model-analysis-00.txt, Sept. 6, 2006]


IPv6 Neighbor Discovery Service

Router (ACR)/Prefix/Parameters Discovery How to deliver Router (ACR) information, On-link Preifx,

Link MTU to PSS? Original

Unsolicited RA or RS/RA exchange in multicast manner WiMAX/WiBro Approach

Unsolicited Unicast RA when PSS attaches to network RS/RA exchange in unicast manner

PSSs may use a prefix for address autoconfiguration but not for on-link determination.

ValidValid LifetimeLifetime

TypeType LengthLength PrefixPrefix LengthLength AA Res 1Res 1LL II

PreferredPreferred LifetimeLifetime

Reserved 2Reserved 2

PrefixPrefixPIO (Prefix Information Option) without setting on link flag (L-bit).



Stateless Address Auto-configuration & DAD Should we support “stateless auto-conf.” in WiBro? If it is needed, how to provide it?

How to DAD How to notify ACR’s CS layer of the auto-configured address?

Original PSS makes a new address by combining an on-link prefix and

its identifier NS/NA Exchange for DAD in multicast manner It takes 1 sec.

WiMAX/WiBro Approach Relay DAD

Omniscient ACR knows about all PSSs’ addresses attached to itself ACR may relay DAD messages to the destination


Next-hop Determination & (Neighbor) Address Resolution

Next-hop Determination Mapping: Destination IPv6 Address → A Neighbor or A router?

Address Resolution Mapping: A Neighbor or A router → Link-layer Address (MAC)

Original NS/NA exchange in multicast manner

WiMAX/WiBro Approach ACR is the only neighbor for a PSS It’s simple



Neighbor Unreachability Detection How to know whether a neighbor node is reachable? Original

NS/NA exchange in unicast manner WiMAX/WiBro Approach

ACR is the only neighbor for a PSS It’s simple We may do this from link-layer event notification without NS/NA

exchange.

Redirect ACR notifies a PSS of the better next-hop Original

Redirect message delivery in unicast manner WiMAX/WiBro Approach

ACR is the only neighbor for a PSS No Use



Standardization TrendsIETF

16ng WG – IPv6 over IEEE 802.16 2 번의 BoF 이후 2006 년 7 월에 신설 – 매번 100 여명 참여 한국 연구자들이 주도적으로 참여 – 삼성전자 의장 2007~2008 년 : 관련 드래프트들의 RFC 화

MIPSHOP WG FMIPv6 over IEEE 802.16e ( 삼성 , ETRI, 한국기술교대 ) WG Item 채택

v6ops WG IPv6 Deployment Scenario over IEEE 802.16e Link (ETRI, 한국기술교대 ) WG Item

채택

WiMAX NWG (Network WG)

2006 년 IPv6 Subteam 의 작업을 통하여 IPv6 및 (Proxy) Mobile IPv6 기술이 최종 문서에 반영

IETF 16ng 의 결과를 WiMAX 에서 활용하려고 함

TTA WiBro6 WG (IPv6 PG – PG210)

2005 년 10 월경 신설 - 2006 년 국내 고유 표준 제정 , 2007 년 현재 Phase II 작업 시작 Phase II 작업은 Proxy Mobile IPv6 을 중심으로 작업

IPv6 Forum Korea Mobility WG

IPv6 over IEEE802.16 연구 , WiBro 망에만 한정된 연구가 아님


Why Network-based IP Mobility?Host-based Mobile IPv4/v6 (RFC 3344/3775) has not been yet deployed that much.

Why host-based MIP is not deployed yet? Too heavy specification to be implemented at a small terminal

RFC 3344 (MIPv4): 99 pages RFC 3775 (MIPv6): 165 pages

Battery problem Waste of air resource

No Stable MIPv4/v6 stack executed in Microsoft Windows OS


Why Network-based IP Mobility?WLAN switch device starts to provide link specific and proprietary solution for IP handover.

No change in MN protocol stack required!

Layer 3 fast secure roaming

The solution works by tunneling traffic from the access point to theWLSM through your Layer 3 core network. No changes to the client devices or the underlying infrastructure are required


Why Network-based IP Mobility?3GPP, 3GPP2 and WiMAX operators are now showing their STRONG interests for network-based IP mobility solution They are even now deploying their non-standardized network-based IP mobility solution (not Mobile IPv4/v6!).

“3gpp and 3gpp2 have official liaisons to the IETF. 3gpp2 communicated through an official liaison before our

session in San Diego that they would like the IETF to produce a standard for proxy MIP. 3gpp maintains a list of what they

would like to see from the IETF and they have also communicated their desire to see a standard for PMIP. The IETF does not have an official liaison relationship with the WiMAX forum. They nonetheless sent a message about what they would like to see and some questions. All this information has already been posted here, on the mailing

list.”

- Phil and Vidya(March 10, 2007)

A message from the chair of netlmm WG


Why Network-based IP Mobility?Operator’s favoritism

Network-based XXX managed by operator itself. However… the opinions are varying…

IETF NetLMM WG started to standardize a network-based mobility management protocol.

63th IETF (2005.7) The first NetLMM BoF

64th IETF (2005.11) The second NetLMM BoF

65th IETF (2006.03) The first NetLMM WG

66th,67th,68thIETF (2006.07, 2006.11, 2007.03) The one of very active WGs in IETF meetings Almost 150~200 persons usually participates in the NetLMM WG


Proxy MIPv6 OverviewIETF Draft History

S. Gundavelli (CISCO), K. Leung (CISCO), and V. Devarapalli (Azaire Networks), “Proxy Mobile IPv6,” draft-sgundave-mipv6-proxymipv6-00, October 16, 2006.

S. Gundavelli (CISCO), K. Leung (CISCO), and V. Devarapalli (Azaire Networks), K. Chowdhury (Starent Networks), “Proxy Mobile IPv6,” draft-sgundave-mipv6-proxymipv6-01, January 5, 2007.

S. Gundavelli (CISCO), K. Leung (CISCO), and V. Devarapalli (Azaire Networks), K. Chowdhury (Starent Networks), B. Patil (Nokia), “Proxy Mobile IPv6,” draft-sgundave-mipv6-proxymipv6-02, March 5, 2007.

GOAL This protocol is for providing mobility support to any IPv6 host within a

restricted and topologically localized portion of the network and without requiring the host to participate in any mobility related signaling.


Proxy MIPv6 OverviewHost-based vs. Network-based Mobility

Host-based Mobility Network-based Mobility

AR

HA

Route Update

Movement Movement

HA

Route Update

AR


Proxy MIPv6 OverviewProxy Mobile IPv6 Overview

LMM (Localized Mobility

Management)Domain

MAG1

Host B

Host A

LMA

Proxy Binding Update (PBU)Control message sent out by MAG to LMA to register its correct location

Home NetworkMN’s Home Network (Topological Anchor Point)

Proxy Care of Address (Proxy-CoA)The address of MAG. That will be the tunnel end-point.

IP TunnelA IPinIP tunnel LMA and MAG.

MAG2

LMA: Localized Mobility AgentMAG: Mobile Access Gateway

LMA Address (LMAA)That will be the tunnel entry-point.

MN’s Home Network Prefix (MN-HNP)CAFE:2:/64

MN’s Home Network Prefix (MN-HNP)CAFE:1:/64

MN Home Address (MN-HoA)MN continues to use it as long as it roams within a same domain


Proxy MIPv6 OverviewNo host stack change for IP mobility

Avoiding tunneling overhead over the air

Re-use of Mobile IPv6 PMIPv6 is based on Mobile IPv6 [RFC3775].

Mobile IPv6 is a very mature mobility protocol for IPv6. Reuse of Mobile IPv6’s home agent functionality and the

messages/format used in mobility signaling. Numerous Mobile IPv6 enhancement can be re-used.

PMIPv6 provides solution to a real deployment problem.

Home in any placeOnly supports Per-MN-Prefix model

Unique home network prefix assigned for each MN. The prefix follows the MN.


ConclusionsIPv6 over WiBro

Wibro 시스템에 최적화된 IPv6 Protocols 의 Adaptation 기술 개발 국내 고유 표준 개발

TTA IPv6 PG 산하 WiBro6 표준 , IPv6 Forum 표준 국제 표준화 선도

IETF 16ng, WiMAX 등

PMIPv6 is New Idea? Absolutely No! Not new idea, but new trend!. It’s a turn for the better!

PMIPv6 is a good example of compromise Until now, long confrontation

Telecommunication Operators Internet Developers and Users PMIP is a good example of compromise

It is still RFC 3775 MIP-based one. But, it follows telco’s favoritism!

Many SDOs STRONGLY like PMIPv6! PMIPv6 over WiBro

high mobility 를 지원하는 ipv6 기술 : ipv6 over wibro internet computing laboratory @ kut ()...

Documents