1. 1 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Mobile IP Multicasting with Host Mobility Locality Gihwan Cho ghcho@cs.chonbuk.ac.kr Chonbuk University

2. 2 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Outline  Internet host mobility support  Multicasting  Problems identified  Existing works  Host movement locality approach Reference 1. A. Acharya, A. Bakre and B. R. Badrinath, “IP Multicast Extensions for Mobile Internetworking,” IEEE INFOCOM’96, 1996, pp.67-75 2. V. Chikarmane et al. “Multicast Support for Mobile Hosts Using Mobile IP: Design Issues and Proposed Architecture,” ACM/Baltzer Mobile Networking and Applications, 3(4), pp.365-379, Jan. 1999 3. S. Deering, “Host Extensions for IP Multicasting,” RFC 1112, Aug. 1989 4. C. Perkins, “IP Mobility Support,” RFC 2002, Oct. 1996

3. 3 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Internet Host Mobility Support  Prerequisite sender may (need) not know the destination is moving datagrams are routed based on IP address  Mobile IP aims to allow transparent routing of datagrams to mobile hosts in the Internet  Three protocol steps agent discovery location registration datagram tunneling

4. 4 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Triangle Routing Internet MA k MA pMA s {MH k, -} MA a {MH a, *} MH a MH k {MH k, *} MH k Registration {MH k, MA s} MH k Discovery Tunneling {MH k, MA s} MH k {MH k, MA s} MH k

5. 5 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Multicasting  Transmitting the same information to a selective set of destination aims to resource saving by arranging for network links to be shared  Two building blocks membership management : IGMP multicast routing protocol : DVMRP, CBT, PIM  DVMRP composes a multicast tree of the reverse shortest paths from each destination to the source

6. 6 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 IGMP & DVMRP MR prune Membership query and reply Membership query and reply graft

7. 7 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Tunnel Convergence Problem  When multicasting meets Internet host mobility support MR MA_a MH_a MH_s1 MH_s2 MA_k MA_s

8. 8 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 In Addition,  With mobility, delay and disconnection MA n MA k MA i MH i1 MA p MH k3 MH k2 MH k1 received twice partially received not received partially received disconnection orphan packet

9. 9 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Arup’s Approach  Deliver datagrams to all subnets do not need to rebuild the multicast tree for host moves MR MA_a MH_a MH_s1 MH_s2 MA_k MA_s

10. 10 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Vineet’s Approach  Designated multicast service server tried to resolve the tunnel convergence problem MR MA_a MH_a MH_s1 MH_s2 MA_k MA_s Designated Tunneling server Designated Tunneling server

11. 11 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Host Mobility Locality  Boring professor model Computing Science (4 days) Computing Center (1/2 day) Company (1 day)

12. 12 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Basic Idea  Find just the places where it is highly likely to be effectively utilized for packet routing  Local region for each mobile host a set of subnets which the mobile host moves often as a technical definition, a set of subnets that are visited by the host during the most recent time,  t then, our approach is to keep multicast paths for each of these subnets during  t as a result, the multicast routes may remain unchanged upon the host’s move, as long as the host moves around within the local region

13. 13 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Local Region MR HA_a MH_a MH_s1 MH_s2 MA_k HA_s Local Region for MH_a

14. 14 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Protocol Overview  Each MA maintains a group view table  Each MH maintains a group view list  Each subnet within a local region maintains the corresponding group view table until the life_time expires  When a host moves out its local region, the previous MA forwards in-flight datagrams to current MA until the forwarding_time expires

15. 15 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Handoff Procedure Current MA HA Previous MA MH Refreshes forwarding_time Registration Req. Registration Rep. Forwarding Rep. Forwarding Req. Starts Join operation Compares {MH’s gourp list, MA’s group view} Creates MH’s group view Finish Join operation Expire forwarding_time Forwarding period from the previous MA Multicast tree join period

16. 16 Chonbuk University, DCLAB, ghcho APCC : Wireless Internet Nov. 2, 2000 Summary  Internet multicast supporting host mobility brings new challenges as: tunnel convergence triangle routing delivery semantics: not, duplicated, partial orphan packet