1. Adaptive Context Transfer Scheme for Fast Handoff in Proxy Mobile IPv6 Sept. 19, 2008 Jaejong Baek, Jooseok Song {jjb27, jssong}@emerald.yonsei.ac.kr Department of Computer Science Yonsei University, Seoul, Korea NGMAST2008

2. Contents Introduction Related work  PMIPv6  Context Transfer Protocol Proposed Schemes  Proactive Handoff scheme  Reactive Handoff scheme  Inter Domain handoff scheme Performance Evaluatoin Conclusion and Future work Q&A 2

3. Abstract Goal  Propose a new scheme for reducing the handoff latency in network-based mobility scenarios based on Proxy Mobile IPv6 Ideas  The integration between PMIPv6 and Context transfer scheme  How the context transfer protocol can be achieved in a PMIPv6 enabled network Result  Reduce handoff latencies based on adaptive transferring of context information. 3 Introduction(1)

4. Keywords PMIPv6  IETF : NETLMM working Group  RFC 5213, Aug, 2008 “Proxy Mobile IPv6”, S. gundavelli. Ed. Context Transfer Protocol  RFC 4067 : basic and generic protocol operation between access routers to perform context transfer 4 Introduction(2)

5. Mobility concept & definitions Terminal mobility  Ability for a terminal to change network point of attachment  Discrete terminal mobility  Continuous terminal mobility(Handover) User mobility  Defined as the ability for a user to maintain the same user identity irrespective of terminals and terminal types Service mobility  Ability for a user to use the particular(subscribed) service irrespective of the user location and the terminal that is used for that purpose. 5 Introduction(3)

6. Handoff types Type(a)  Mobile-controlled handoff The MN has the primary control over the handover process  Network-controlled handoff The network has the primary control over the handover process Type(b)  Proactive(Planned) handoff A proactive(expected) handover where some signaling can be done in advance of the MN getting connected to the new AR, e.g., building a temporary tunnel from the previous AR to the new AR  Reactive(Unplanned) handoff A reactive(unexpected) handover where no signaling is done in advance of the MN’s move from the previous AR to the new AR 6 Introduction(4)

7. Why Network-based? Host-based Mobile IPv4/v6 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 Battery problem Waste of air resource  No Stable MIPv4/v6 stack executed in Microsoft Windows OS No change in MN protocol stack required! 7 Related work(1)

8. 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(HNP) assigned for each MN.  The prefix follows the MN. 8 Related work(2)

9. PMIPv6 Architecture 9 LMMD (Localized Mobility Management Domain), PMIPv6 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 Network MN’s Home Network (Topological Anchor Point) Proxy Care of Address (Proxy-CoA) The address of MAG. That will be the tunnel end-point. IP Tunnel A IPinIP tunnel LMA and MAG. MAG2 LMA: Localized Mobility Anchor MAG: 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 Related work(3)

10. Context Transfer Protocol Goal  to quickly re-establish context transfer-candidate services without requiring the MN to explicitly perform all protocol flows for those services.  to provide an interoperable solution that supports various Layer 2 radio access technologies 10 Related work(4) AR pMAG AR nMAG CONTEXT MN LMA

11. Predictive CTD 11 Network controlled, initiated by pAR n/pAR : new/previous Access Router CTD : CT Data  Feature context (MN’s previous IP and parameters for nAR)  which will be used in authentication of MN’s identity CTAR : CT Activate Request, CTDR : CTD Reply Related work(5)

12. Reactive CTD Network controlled, initiated by nAR CT-Req message CTD  MN’s previous IP, Feature Context, sequence #, authorization token 12 Related work(5)

13. PMIPv6 Signaling Flow(1) PMIPv6  MN Attachment - Signaling Flow 13 Related work(6) PBU : Proxy Binding Update PBA : Proxy Binding Ack BCE : Binding Cache Entry HNP : Home Netwok Prefix

14. PMIPv6 Signaling Flow(2)  MN Handoff - Signaling Flow 14 Related work(7)

15. Proactive Handoff Scheme 15 Proposed schemes(1) Authentication information - MN-ID, shared secret key Authorization information - Lists of authorized services Accounting information. - Usage record of resources and services

16. Reactive Handoff Scheme 16 Proposed schemes(2)

17. Inter domain handoff scheme 17 Proposed schemes(3)

18. Analytic modeling Cost functions(MIPv6 vs Proposed)  Location update(C L ) Existing : Proposed :  Packet delivery(C P ) Existing : Proposed :  Total cost : C T = C L + C P 18 Performance evaluation(1)

19. Notations : the average number of LMD crossings : the number of CNs. : the location update cost to the HA : the location update cost to the CN : the location update cost to the LMA : the packet delivery cost through the LMA : the packet arrival rate through the new LMA : the packet arrival rate through the old LMA : the average session size = 1.5 : the packet tunnel cost 19 Performance evaluation(2)

20. Comparison 20 Total cost for inter-domain handoff Performance evaluation(1)

21. Conclusion and Future Work Network-based localized mobility management  Proactive and reactive schemes.  adaptive context transfer schemes Context transfer protocol reduces the inter and intra handoff latency by avoiding the re-initiation of signaling to and from the MN. In the future  we will focus on the detail message structure like how it will be implemented without modifications on the current PMIPv6 architecture and present performance results to assess the effectiveness of this scheme. 21

22. References [1] J. Lougney, M. Nakhjiri, C. Perkins, and R. Koodli,“Context Transfer Protocol (CXTP),” RFC 4067, IETF,July 2005, Tech. Rep. [2] P. De Silva and H. Sirisena, “A mobility management protocol for IP-based cellular networks,” Wireless Communications, IEEE [see also IEEE Personal Communications], vol. 9, no. 3, 2002. [3] S. Gundavelli and K. Leung, “Localized mobility management using proxy mobile IPv6: draft-gundavellinetlmmmip61] J. Lougney, M. Nakhjiri, C. Perkins, and R. Koodli, “Context Transfer Protocol (CXTP),” RFC 4067, IETF, July 2005, Tech. Rep. [2] P. De Silva and H. Sirisena, “A mobility management protocol for IP-based cellular networks,” Wireless Communications, IEEE [see also IEEE Personal Communications], vol. 9, no. 3, 2002. [3] S. Gundavelli and K. Leung, “Localized mobility management using proxy mobile IPv6: draft-gundavellinetlmmmip6- proxy-11. txt,” IETF draft, February,2008. [4] J. Kempf et al., “Goals for Network-based Localized Mobility Management (NETLMM),” RFC 4831, April,2007. [5] H. Duong and S. Dadej, A.and Gordon, “A General Framework for Context Transfer in Mobile IP Networks,” Vehicular Technology Conference, VTC 2006- Spring. IEEE 63rd, vol. 2, pp. 1017–102 176–88, 2006. [6] D. Johnson, C. Perkins, and J. Arkko, “Mobility Support in IPv6,” RFC 3775, June, 2004. [7] C. Politis, K. Chew, N. Akhtar, M. Georgiades, R. Tafazolli, and T. Dagiuklas, “Hybrid multilayer mobility management with AAA context transfer capabilities for all-IP networks,” Wireless Communications, IEEE [see also IEEE Personal Communications], vol. 11, no. 4, pp. 76–88, 2004. [8] M. Georgiades, N. Akhtar, C. Politis, and R. Tafazolli, “Enhancing mobility management protocols to minimise AAA impact on handoff performance,” Computer Communications, vol. 30, no. 3, pp. 608–618, 2007. 22

23. Q&A 23