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네트워크 기반 지역 이동성 지원 프로토콜 적용 기술. Internet Computing Laboratory @ KUT ( http://icl.kut.ac.kr ) Youn-Hee Han. Why Network-based?. Host-based Mobile IPv4/v6 (RFC 3344/3775) has not been yet deployed that much. Why host-based MIP is not deployed yet?
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네트워크 기반 지역 이동성 지원 프로토콜 적용 기술 Internet Computing Laboratory @ KUT (http://icl.kut.ac.kr) Youn-Hee Han
Why Network-based? • 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 IT Forum Korea 2007
Why Network-based? • 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 the WLSM through your Layer 3 core network. No changes to the client devices or the underlying infrastructure are required IT Forum Korea 2007
Why Network-based? • 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!). A message from the chair of netlmm WG “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) IT Forum Korea 2007
Why Network-based? • 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 IT Forum Korea 2007
IETF Activities • Before 67th IETF Meeting (Nov. 5~10, 2006) • IETF MIPv6 WG • Proxy Mobile IPv6 • draft-sgundave-mipv6-proxymipv6 • draft-chowdhury-netmip6-01 • IETF NetLMM WG • DT (Design Team) Solution • draft-giaretta-netlmm-dt-protocol • draft-akiyoshi-netlmm-protocol • draft-giaretta-netlmm-protocol • draft-gundavelli-netlmm-mip6-proxy • draft-raman-netlmm-protocol • draft-templin-autoconf-netlmm-dhcp • draft-vidya-netlmm-netmob • draft-wanghui-netlmm-protocol • DHCP-based solution • draft-templin-autoconf-netlmm-dhcp • In MIPv6/NetLMM WG mailing list, so much mailing discussion!!! IT Forum Korea 2007
IETF Activities • During 67th IETF Meeting • IETF NetLMM WG • Proxy Mobile IPv6 • draft-sgundave-mipv6-proxymipv6 (First Author – Cisco) [1] • draft-chowdhury-netmip6-01 (First Author – Starent Networks) [2] • DT (Design Team) Solution • draft-giaretta-netlmm-dt-protocol (First Author – Ericsson) [3] • DHCP-based solution • draft-templin-autoconf-netlmm-dhcp (First Author – Boeing) [4] • Before voting, there are already many input from other SDOs • 3GPP2 Correspondence to IETF on NetLMM WG • “3GPP2 has made a decision to use the Proxy Mobile IP concept as a network based mobility management solution.” • Voice of a person from WiMAX • “WiMAX adopted PMIP. PLEASE make it standardized in IETF.” IT Forum Korea 2007
IETF Activities • Voting Results • Vote 1: NETLMM WG should adopt more than one draft. • Overwhelming support against Just one solution! • Vote 2: Which one is our solution? • A Proxy MIPv6, [1] or [2]: 45 peoples So, PMIP is selected! • DT Solution, [3]: 30 peoples • DHCP-based Solution, [4]: 10 peoples • Vote 3: Then, which PMIP is adopted as a starting point? • [1]: 18 peoples • [2]: 7 peoples • Abstain and wait: 28 peoples IT Forum Korea 2007
Proxy MIPv6 Goal • IETF 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. IT Forum Korea 2007
Technical Background • Host-based vs. Network-based Mobility HA HA Route Update Route Update AR AR Movement Movement Network-based Mobility Host-based Mobility IT Forum Korea 2007
Proxy MIPv6 Overview • Proxy Mobile IPv6 Overview LMA: Localized Mobility AgentMAG: Mobile Access Gateway IP Tunnel A IPinIP tunnel LMA and MAG. LMA Home NetworkMN’s Home Network (Topological Anchor Point) MN’s Home Network Prefix (MN-HNP) CAFE:1:/64 MAG1 Host A LMA Address (LMAA) That will be the tunnel entry-point. LMM (Localized Mobility Management)Domain MAG2 MN’s Home Network Prefix (MN-HNP) CAFE:2:/64 Proxy Binding Update (PBU) Control message sent out by MAG to LMA to register its correct location Host B 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. IT Forum Korea 2007
Proxy MIPv6 Overview • No 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. • Only supports Per-MN-Prefix model • Unique home network prefix assigned for each MN. • The prefix follows the MN. IT Forum Korea 2007
Proxy MIPv6 Overview • Home in Any Place • MN will always obtain its “home-address”, any where in the network. • A new function, Mobile Access Gateway (MAG), that runs on the access router will emulate the home link on its access link. • It will ensure that MN believes it is at its home. • MN Home Network Prefix • MN Home Address • LMA Address • Address Configuration Mode • Roaming Policy • … IT Forum Korea 2007
Proxy MIPv6 Overview • Rough Procedure • MN moves and attaches to an access router • After access authentication, MAG (access router) identifies MN • MAG obtains MN’s profile containing the Home Address ..etc • MAG sends the Proxy Binding Update to LMA on behalf of MN • MAG receives the Proxy Binding Ack. from LMA • MAG sends Router Advertisements containing MN’s home network prefix • Stateless Case • MN will still configure (or maintain) the same as its home address. • Stateful Case: • the network will ensure that it always gets its home address. IT Forum Korea 2007
Proxy MIPv6 Overview MN can now use its home address for the same domain This can be omitted when stateless configuration is used. Tunnel Setup MAG emulates the MN’s home link IT Forum Korea 2007
LMA Operation • LMA Operation (1/2) • LMA needs to understand the Proxy Registration. • It has to modify the typical RFC 3775 trust model to support Proxy Model. Proxy Binding Update Proxy Binding Acknowledgement IT Forum Korea 2007
LMA Operation • LMA Operation (2/2) • LMA-MAG tunnel is a shared tunnel among many MNs. • 1:1 relation m:1 relation • One tunnel is associated to multiple MNs’ Binding Caches. • Life-time of a tunnel should not be dependent on the life time of any single BCE. • LMA will add prefix routes to MN’s home network prefix over the tunnel. IT Forum Korea 2007
MAG Operation • MAG Operation • It emulates the home link for eachMN. • After the access authentication, MAG will obtain MN’s profile which contains: • MN’s home address • MN’s home network prefix • LMA address ..etc. • It establishes a IPv6/IPv6 tunnel with the LMA. • All the packets from MN are reverse tunneled to its LMA • All the packets from the tunnel are routed to MN. • Router Advertisement should be UNICASTed to an MN • It will contain MN’s Home Network Prefix (MN-HNP) IT Forum Korea 2007
MN Operation • MN Operation • Any MN is just a IPv6 host with its protocol operation consistent with the base IPv6 specification. • All aspects of Neighbor Discovery Protocol will not change. • When MN attaches to a new AR, it receives a Router Advertisement message from the AR with its home prefix. • Throughout the PMIP domain, MN using DHCP procedure or in stateless address configuration mode, will obtain the same home address. IT Forum Korea 2007
Data Transport • Data Transport • LMA-MAG Tunneling/Reverse Tunneling MAG CN MN LMA MN sends a packet to CN MAG forwards to LMA LMA sends to CN CN sends packet to MN LMA forwards to MAG MAG sends to MN IT Forum Korea 2007
internet IPv4 Support • PMIPv6 will support IPv4 Access Network may be IPv4, Private IPv4 , IPv6, or Both IPv4 and IPv6 Dual Stackentity 3 MAG LMA MN Dual Stackentity IPv4 only, IPv6 only, or Dual Stack Transport network can be IPv4 only, IPv6 only or DS IPv4/IPv6 • Support for IPv4 only hosts and support for IPv4-HoA for Dual Stack hosts • Support for IPv4 at the MAG and LMA to deal with the transport network • Support IPv4-HoA and binding at the LMA for hosts requesting an IPv4 address IT Forum Korea 2007
Conclusions • 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! • Future Work Items • PMIPv6 over IEEE 802.16/WiBro • Fast Handover in PMIPv6 • Route Optimization in PMIPv6 • PMIPv6-based NeMo IT Forum Korea 2007