On Mobile IPv6 Optimization and Multihoming draft-ng-mobopts-multihoming-00.txt

1. On Mobile IPv6 Optimization and Multihomingdraft-ng-mobopts-multihoming-00.txt Chan-Wah Ng chanwah.ng@sg.panasonic.com Keigo Aso asou.keigo@jp.panasonic.com IETF70 - Mobopts RG

2. Agenda • Background • Scenario: Multihomed Correspondent Node • Problem with Route Optimization • Possible Enhancement Approaches IETF70 - Mobopts RG

3. Background • Mobility and multihoming is getting more and more common • An excellent discussion on their interactions • draft-vidya-ip-mobility-multihoming-interactions-01.txt • Focus here is more on the performance of Mobile IPv6 when: • Mobile node is multihomed • Anchor point is multihomed • Correspondent node is multihomed • Possibly to extend RFC4651 IETF70 - Mobopts RG

4. INTERNET INTERNET CN’s Network MN MN ER ER P2 P1 P1 P2 CN CN Scenario: Multihomed CN • CN is multihomed: • CN is on an multihomed site • CN has multiple interfaces IETF70 - Mobopts RG

5. INTERNET INTERNET App1 App2 App1 App2 App App TCP/UDP TCP/UDP SCTP/SHIM6 SCTP/SHIM6 P2::CN P2::CN P1::CN P1::CN MN CN MN CN Scenario: Multihomed CN • CN uses multiple addresses when communicating with MN • Single Session • Using SCTP or SHIM6 • Multiple Sessions • Application-level flow distribution • Different applications IETF70 - Mobopts RG

6. Problem with Route Optimization • The MIPv6 layer at MN has no way of knowing that P1::CN and P2::CN belongs to the same node • When route optimization is triggered, MN would • Trigger RR and send BU to P1::CN • Trigger RR and send BU to P2::CN CN MN P2::CN P1::CN HoTI HoT CoTI CoT BU BA HoTI HoT CoTI CoT BU Redundant!!! BA IETF70 - Mobopts RG

7. Resolution • Principle • Make Mobile IPv6 Layer aware of CN’s multihoming • Two main approaches • Inter-layer APIs • MIPv6 RO Signaling IETF70 - Mobopts RG

8. Inter-Layer APIs • Allow applications or transport/SHIM layers to notify Mobile IPv6 layer • A list of addresses that are linked • CoA bindings at any address implies all CoA bindings at all linked address • Pros • Simple, no protocol extension • Cons • Applications, transport layers need to be changed • Does not work with multiple applications IETF70 - Mobopts RG

9. Protocol Extension • CN informs MN of its multiple addresses • After receiving HoTI/CoTI/BU • Response with list of addresses in HoT/CoT/BA • Pros • Works for all applications • Cons • Protocol extension needed • Requires more in depth considerations IETF70 - Mobopts RG

10. Protocol Extension (cont’d) • Design points to consider: • Which message to include the list of addresses? • HoT, CoT, BA? • Notify all MNs or selectively? • How to select? • Security consideration • Threats on MN? • Fake list of linked address • Threats on CN? • Reveal all of CN’s addresses IETF70 - Mobopts RG

11. Discussion • Is this work worth looking into in IRTF/IETF community? • Only multihomed CN is analyzed • Two more cases • multihomed MN • multihomed anchor points (eg. HA, MAP) • Any similar work being done? IETF70 - Mobopts RG