1. IP Mobility Management - 핵심 기술 및 최신 표준 동향 -
Youn-Hee Han
Korea University of Technology and Education Laboratory of Intelligent Networks
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2. Outline Network-based IP Mobility Support
Dual-Stack Support in Network-based IP Mobility
Network-based Mobility Optimization
New Issues and Summary
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3. Network-based IP Mobility Support
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4. Recent Trend of IP Mobility
Network-based!
No change to host
Mobility handled by the network, often transparent to the host
IETF’s much activities
Working Groups
NetLMM (Proxy Mobile IP), NetExt, Mext, Mipshop, Mif, Mip4
BoF
NetExt2
3GPP/PP2 and WiMAX operators are now showing their STRONG interests for network-based IP mobility solution
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5. Why Network-based?
Host-based IP Mobility (CMIPv4/v6) has not been widely deployed due to several factors
Implementation issues
IPsec and IKEv1
Deployment issues
no cohesive mobility architecture
Negligible deployment of IPv6
Operational issues
Layer 3 signalling via radio link
Layer 8 issues (Financial/Human/Political/FUD/…)
Many operators elected to create their own protocols (eg. GTP), or
They picked other IETF mobility protocols (Proxy MIP etc.)
Money!
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6. No Stable MIPv4/v6 stack executed in Microsoft Windows OS
Why Network-based?
Operators are even now deploying their non-standardized network-based IP mobility solution
[CMIPv6’s Problems]
1) Too heavy specification to be implemented at a small terminal
- RFC 3344 (MIPv4): 99 pages
- RFC 3775 (MIPv6): 165 pages
2) Battery problem
3) Waste of air resource
No Stable MIPv4/v6 stack executed in Microsoft Windows OS
No changes to the client devices or the underlying infrastructure are required
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7. Proxy Mobile IPv6 (PMIPv6)
Proxy Mobile IPv6 [IETF RFC 5213, August 2008]
LMA: Localized Mobility Agent MAG: Mobile Access Gateway
IP Tunnel
IP-in-IP tunnel between LMA and MAG
LMA
Home Network
MN’s Home Network
(Topological Anchor Point)
MAG
LMA Address (LMAA)
That will be the tunnel entry-point
LMM (Localized Mobility Management) Domain
MAG
movement
Proxy Binding Update/Ack. (PBU/PBA)
Control messages exchanged by MAG to LMA to establish a binding between MN-HoA and Proxy-CoA
MN’s Home Network Prefix (MN-HNP)
CAFE:2:/64
MN’ Home Address (MN-HoA)
MN continues to use it as long as it roams within a same domain
Proxy Care of Address (Proxy-CoA)
The address of MAG That will be the tunnel end-point
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8. PMIPv6 Operation Flow MN MAG AAA&Policy Store LMA CN DHCP Server
PBU: Proxy Binding Update PBA: Proxy Binding Ack.
RA*: MN의 Prefix를 Policy Store에서 수신한 경우의 Router Advertisement
RA**: MN의 Prefix를 LMA에서 수신한 경우의 Router Advertisement MN
MAG
AAA&Policy Store
LMA CN
MN Attachment
AAA Query with MN-ID
AAA Reply with Profile
RA*
PBU with MN-ID, Home Network Prefix option, Timestamp option
PBA with MN-ID, Home Network Prefix option
RA**
Tunnel Setup
Optional
DHCP Server
DHCP Request
DHCP Request
DHCP Response
DHCP Response
[MN-HoA:CN](data)
[Proxy-CoA:LMAA][MN-HoA:CN](data)
[MN-HoA:CN](data)
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9. PMIPv6 Features Home in Any Place RA Unicast
MAG sends the RA (Router Advertisement) messages advertising MN’s home network prefix and other parameters
MAG will emulate the home link on its access link.
RA Unicast
RA should be UNICASTed to an MN
It will contain MN’s Home Network Prefix
Per-MN Prefix
Any MN is just a IPv6 host
Any MN is just a IPv6 host with its protocol operation consistent with the base IPv6 specification.
M:1 Tunnel
LMA-MAG tunnel is a shared tunnel among many MNs.
One tunnel is associated to multiple MNs’ Binding Caches.
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10. PMIPv6 over WiBro/WiMAX
Proxy Mobile IPv6 over WiBro/WiMAX
IP Network
Internet
E R
ACR/MAG
L2 Switch
BS/RAS
PSS
HA or LMA
AAA/Policy Store
ACR
DNS
NMS
TTA 단체표준, “와이브로에서의 프록시 모바일 IPv6 적용,” TTAK.KO , Dec. 2008
"WiMAX Forum Network Architecture (Stage 3: Detailed Protocols and Procedures) Release 1 Version 1.2.3“, Jul 2008.
Previous MAG
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11. PMIPv4 over WiMAX In Split PMA (Proxy Mobility Agent  MAG & FA) Model
“WiMAX Forum/3GPP2 Proxy Mobile IPv4,” IETF Internet Draft - draft-leung-mip4-proxy-mode-10.txt
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12. PMIPv6 in 3GPP LTE/EPC Proxy Mobile IPv6 over LTE
AAA/ Policy Server
Ref.] I. Guardini et al., “Mobile IPv6 deployment opportunities in next generation 3GPP networks,” 16th IST Mobile&Wireless Communication Summit, Budapest, Hungary 1-5, July 2007
GTP-U Tunnel
IP-in-IP Tunnel UE
eNodeB
S-GW/(MAG)
P-GW/LMA
P-GW: access gateway towards Packet Data Networks (similar to the GGSN)
Optional!
- PMIPv6 will be mainly used for inter-system handovers (i.e. handovers between 3GPP and non-3GPP accesses)
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13. PMIPv6 in 3GPP LTE/EPC Proxy Mobile IPv6 over LTE
Vertical handover scenario
LMA
LMA
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14. Dual-Stack Support in Network-based IP Mobility
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15. Current Solutions & Problems
Current (Bad) Solutions in Host-based MIPv6  Two IP Mobility Stacks MN
Mobile IPv4 (RFC3344) & Mobile IPv6 (RFC3775)을 동시에 구현 HA
Mobile IPv4 & Mobile IPv6 각각에 대한 HA를 운영
Problems
IPv4IPv6 (or IPv4IPv6) 망간 이동시 세션 유지 불가능
구현(Implementation)의 어려움
두 개의 프로토콜을 동시에 구현  단말 및 장비의 단가 향상
운영(Operation)의 어려움
비효율적인 이동성 관리
네트워크 시그널 메시지의 오버헤드
So… alterative Solution:
DS (Dual-Stack)-MIPv6: RFC 5555
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16. DS-MIPv6 Goal & Design Principle
설계 목표
IPv4 및 IPv6 이동성을 위하여 하나의 통합된 이동성 관리 프로토콜 설계
Mobile IPv6를 확장하여 다음 두 가지를 만족한다.
IPv4 Transport Network Support
IPv4 Home Address Mobility
설계 원칙
MN은 IPv4 HoA/CoA 및 IPv6 HoA/CoA 에 대한 바인딩 정보를 함께 HA에 등록을 한다.
임의의 IPv4 or IPv6 or IPv4/v6 Dual 네트워크로 이동하더라도 IPv4 or IPv6 패킷을 받을 수 있도록 한다.
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17. Dual Stack Support in PMIPv6
Dual-Stack Support in Proxy MIPv6
draft-ietf-netlmm-pmip6-ipv4-support-14.txt (July 2009)
PMIPv6 기반 IPv4 Transport 지원 + IPv4 Home Address Mobility 지원
DS-MIPv6와 같은 설계 목표와 원칙
DS-PMIPv6가 고려하는 시나리오
Cellular
IP network
WLAN IP Network
WiBro
IP Network
RAS
LTE BS
WLAN AP
IPv4
IPv6
Private IPv4
NAT
AAA
DS-PMIPv6 LMA
IPv4 Application (VoD, IP-Phone…)
IPv6 Application (VoD, IP-Phone…) MN
DS-PMIPv6 MAG
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18. DS(Dual Stack)-PMIPv6 PMIPv6’s Dual-Stack Support
[Mobility Binding]
HoAv4 and HoAv6
Dual Stack MN or IPv4 MN
PBU (HoAv6, Proxy CoAv6, HoAv4)
Proxy CoAv6
IPv4 traffic
CNv4  HoAv4
IPv6 Tunnel (LMAAv6Proxy CoAv6)
IPv6 traffic
CNv6->HoAv6
Dual Stack MAG
Only-IPv6 enabled
(Proxy CoAv6)
Dual Stack LMA
Only-IPv6 enabled
(LMMAv6)
<MN in IPv6 domain>
[Mobility Binding]
HoAv4 and HoAv6
Dual Stack MN or IPv4 MN
PBU (HoAv6, Proxy CoAv4, HoAv4)
Proxy CoAv4
IPv4 traffic
CNv4  HoAv4
IPv4 Tunnel (LMAAv4Proxy CoAv4)
IPv6 traffic
CNv6->HoAv6
Dual Stack MAG
Only-IPv4 enabled
(Proxy CoAv4)
Dual Stack LMA
Only-IPv4 enabled
(LMAAv4)
<MN in IPv4 domain>
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19. DS(Dual Stack)-PMIPv6
MAG와 LMA 사이의 시그널링 및 터널 설정
LMA (바인딩 관리: IPv6 HoA & IPv4 HoA  IPv4 or IPv6 Proxy-CoA )
IPv4-UDP-IPv6-PBU
IPv4-UDP-IPv6-PBU
IPv6-PBU
IPv6-PBAck
IPv4-UDP-IPv6-PBAck
IPv4-UDP-IPv6-PBAck
NAT
6-in-6 Tunnel
4-in-6 Tunnel
6-in-4 Tunnel
4-in-4 Tunnel
6-in-udp-in-4 Tunnel
4-in-udp-in-4 Tunnel
MAG
MAG
MAG
MN 이 IPv6 네트워크로 이동할 때
MN 이 IPv4 네트워크로 이동할 때
MN 이 Private IPv4 네트워크로 이동할 때
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20. LMA가 MN에게 할당할 Prefix Pool
DS-PMIPv6 테스트베드-1
v4/v6 VoD Server CN
ETRI (2007,2008)
eth1)
3ffe:2::1/64
LMA
MN has Dual Stack and both addresses are always enabled
V4/V6 network
eth0)
3ffe:2::2/64
LMA가 MN에게 할당할 Prefix Pool
3ffe:1:3:1::/64 ~
3ffe:1:3:ffff::/64
eth0)
3ffe:1::1/64
NAT
Private V4 network
V6 network
eth0)
V4 network
MAG3
eth0) 3ffe:1::2/64
MAG1
eth0)
MAG2
ra0)
3ffe:1:3::1/64
fe80::1
ra0)
3ffe:1:1::1/64
fe80::1
ra0)
3ffe:1:2::1/64
fe80::1
SSID: PMIP3
SSID: PMIP1
SSID: PMIP2
초기 실행: v4 VoD Client
초기 실행: v6 VoD Client
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21. DS-PMIPv6 테스트베드-2
KT (2007): DS-PMIPv6 with Only Private IPv4 Network and IPv4 Application
LMA
(PC0)
VoD
(PC4)
Subnet 4
NAT1
NAT2
MAG1
(PC1)
MAG2
(PC2)
Subnet 1
Subnet 2
MAG3
(PC3)
Subnet 3
Notebook1
Notebook2
802.11g
802.11a
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22. Test: MIPv6 vs. PMIPv6
Test Results with Heavy Traffic (presented at MobiWorld 2008 conference)
Encoding Rate: 2Mbps
UDP Throughput of MIPv6
UDP Throughput of PMIPv6
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23. Network-based Mobility Optimization
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24. Network-based Handover Optimization
네트워크 기반의 IP Handover 기술 및 최적화
Basic Standard
Proxy Mobile IPv6 (PMIPv6) – RFC 5213 (Aug. 2008)
Base Protocol
IETF의 네트워크 기반 핸드오버 최적화 기술
Fast Handovers for Proxy Mobile IPv6 (F-PMIPv6)
draft-ietf-mipshop-pfmipv6-04.txt (May 2009)
핸드오버시 라우터간 터널링 기술
Transient Binding for Proxy Mobile IPv6 (TB-PMIPv6)
draft-ietf-mipshop-transient-bce-pmipv6-02.txt (March 2009)
Make-before-break 핸드오버시 두 개의 인터페이스를 동시에 사용할 수 있는 기술
L2 handover
MD (필요없음), DAD (생략가능), Network-based BU
[PMIPv6]
time
Layer 2+3 Latency
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25. Fast Handover for PMIPv6
F-PMIPv6 Procedure
Access technology specific (out of scope)
(Tunnel Setup)
NAR requests PAR to forward or buffer the packets & Tunnel Setup (When?  out of scope)
Forwarding
(Buffering at NAR)
Access technology specific (out of scope)
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26. Fast Handover for PMIPv6
PMIPv6 vs. F-PMIPv6
HO-INITIATE
HO-COMPLETE (Link-UP)
Link-specific Handover MN
PBU
PBAck
LMA
Old MAG
New MAG
Total Handover Latency
PMIPv6
Link-specific Handover MN
PBU
PBAck
LMA
Old MAG
New MAG
Total Handover Latency HI
HAck
Buffering
F-PMIPv6
HO-INITIATE
HO-COMPLETE (Link-UP)
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27. New Issues and Summary
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28. IETF NetEXT2 WG IETF’s New WG – NetExt (NETLMM Extension)
2009년 7월 첫 WG 회의 (75th IETF - Stockholm, Sweden)
PMIPv6에 대한 Extension 기술에 대한 표준화
Work Items on Consensus
Localized routing
bulk-registration
Runtime LMA selection
IETF’s New BoF – NetExt2 (NETLMM Extension 2)
2009년 7월 첫 BoF 회의
More controversial issues
Multiple Interface support
Inter-technology handovers
“Flow Bindings in Mobile IPv6 and NEMO Basic Support”, IETF Internet-Draft, draft-ietf-mext-flow-binding-03.txt, July 2009.
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29. 다른 인터페이스의 스위치 를 올려서 단순하게 접속만 시도했군 ! 세션이동성은 없고…
New Issues in PMIPv6
What Issues in NetEXT2 BoF ?
Scenario 1: Setting up Mobility Sessions on Demand
Create additional mobility sessions on demand
e.g., additional connection for a particular service
A new mobility session with a new prefix is created
LMA
LMA
Mobile IPTV flow
Mobile IPTV flow
PBU (HI=1)
PBU (HI=1)
다른 인터페이스의 스위치 를 올려서 단순하게 접속만 시도했군 ! 세션이동성은 없고…
MAG
MAG
MAG
MAG
VoIP flow
VoIP flow
WiMax 3G
WiMax 3G
HTTP flow
WiBro 3G
WiBro 3G MN MN
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30. 새로운 인터페이스로 세션을 이동하고 있네? Vertical 핸드오버군 !
New Issues in PMIPv6
What Issues in NetEXT2 BoF ?
Scenario 2: Flow Mobility
If another access is enabled on the MN, some of the existing flows could be moved over, to achieve, e.g., load balancing and better user experience
LMA
LMA
Mobile IPTV flow
Mobile IPTV flow
PBU (HI=2)
PBU (HI=1)
새로운 인터페이스로 세션을 이동하고 있네? Vertical 핸드오버군 !
MAG
MAG
MAG
MAG
VoIP flow
VoIP flow
WiMax 3G
WiMax 3G
WiBro 3G
WiBro 3G MN MN
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31. Summary Summary Network-based IP Mobility Management
Proxy Mobile IPv6
Dual Stack Support
IPv4/v6 Transport Network Support
IPv4/v6 Home Address Mobility
Fast Handover in PMIPv6
Cross-layering Issues
Complete Support for Various Vertical Handover Scenario
“Initial Attachment” vs. “Handover”
Per-flow mobility
Network-based Proxy MIPv6
Horizontal Handover
Vertical Handover
Multiple Interface Management
Multiple Flow Management
A handover is initiated when mobile device exits the boundaries of an administrative domain. Single interface is used.
A mobile device does need to move in order to initiate a handover. Multiple interfaces are required, but use one interface at a time.
Simultaneous use of multiple interfaces and access
networks. Association of an application with an interface
Ability to split individual flows between links with
respect to the requirements of the flows and the user
preferences
Complexity Level
IETF New WG - Mif (Multi-interface)
- Interface selection
- Address selection
Host-based MIPv6
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