1. Network Research Lab. Sejong University, Korea Jae-Kwon Seo, Kyung-Geun Lee Sejong University, Korea

2. Network Research Lab. Sejong University, Korea  Introduction  Related works  Proposed scheme  Simulation Experiment  Numerical Analysis  Conclusion 2

3. Network Research Lab. Sejong University, Korea  Mobility support in IPv6 (MIPv6) ◦ Home Agent (HA) ◦ Temporary address, Care-of-Address (CoA) ◦ A mobile node(MN) moves to a foreign network,  Binding update : MN->HA 3

4. Network Research Lab. Sejong University, Korea 4 HA MN CN 1 2 3 5 4 Intercept & Encapsulation ①, ② : Binding Update/Acknowledge ③, ④, ⑤ : First User Data Packet Delivery

5. Network Research Lab. Sejong University, Korea ◦ Authenticating binding-update requires 1.5 RTT between MN and CN ◦ One RTT is needed to update the HA ◦ A Mobile Node has to register to the HA every handover occurs 5

6. Network Research Lab. Sejong University, Korea  Two addresses ◦ Regional CoA (RCoA) : MAP prefix based ◦ On-link CoA (LCoA) : current AR prefix based  Mobility Anchor Point (MAP) ◦ Local HA ◦ Intercepts the packets destined to RCoA ◦ Tunnels the packets to the LCoA  Two binding updates ◦ Regional binding update : RCoA -> HA ◦ Local binding update : LCoA -> MAP 6

7. Network Research Lab. Sejong University, Korea 7 7 MAP HA CN Internet MAP old AR newA R MAP domain MN Local BU (Home address, RCoA) (RCoA, Home BU Local BU LCoA’) LCoA )

8. Network Research Lab. Sejong University, Korea 8 reduces wired signaling cost & reduces update latency MN ARHA or CN MNAR HA or CN MAP MIPv6 HMIPv6

9. Network Research Lab. Sejong University, Korea  Efficiently in supporting micro-mobility ◦ Within a MAP domain  Not appropriate in supporting macro-mobility ◦ Inter-MAP domain handover ◦ longer handover latency with more packet loss 9

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11. Network Research Lab. Sejong University, Korea  Velocity-based MAP selection scheme ◦ Fast MNs select the HMAP ◦ Slow MNs select the LMAP  Load control scheme ◦ The MAP checks the maximum number of MNs ◦ Decides whether to receive or to reject a registration request of the MN ◦ Rejected MN selects the next candidate MAP  Velocity based + load control, velocity based + moving range of the MN… 11

12. Network Research Lab. Sejong University, Korea  Estimated velocity may not reflect the current velocity  MNs do not always move with constant velocity and direction  Slow MN eventually encounters the inter-domain handover but this case is not considered  This paper proposes a MAP changing scheme using a virtual domain (VD) 12

13. Network Research Lab. Sejong University, Korea  Simple method ◦ Considering only current moving direction and position of the MN ◦ Reduces significant overhead generated by complex computation procedure ◦ Not responsible for wrong prediction  Virtual domain ◦ Assigning ARs to the domain of the Higher layer MAP (HMAP) 13

14. Network Research Lab. Sejong University, Korea 14 Changing Point 1 : MN moves to the changing point of the VD 2 : MAP changing request message 3 3 : Binding Update (LCoA) 4 4 : Biding Ack. 5 5 : Binding Update (RCoA) 6 6 : Binding Ack.

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16. Network Research Lab. Sejong University, Korea 16 only

17. Network Research Lab. Sejong University, Korea  The changing point is AP (802.11) or BS(802.16)  The MAP changing procedure is similar to the inter-domain handover ◦ Except for the generating procedure of the LCoA  Inter-domain handover occurs ◦ MN completes the handover using binding update with LCoA only.  Does not generate packet loss ◦ The MAP changing procedure changes the routing path only from CN to MN while receiving packets  Load concentration of a HMAP is distributed in VD ◦ MNs registered with HMAP and LMAP coexist in VD 17

18. Network Research Lab. Sejong University, Korea ◦ Simulation topology  NS-2 18

19. Network Research Lab. Sejong University, Korea  RTT between MN and CN 19 Furthest selection scheme Nearest selection schemeMAP changing scheme

20. Network Research Lab. Sejong University, Korea  When the ping-pong movement occurs 20

21. Network Research Lab. Sejong University, Korea  Average number of the encapsulated packets at HMAP (HMAP load) 21

22. Network Research Lab. Sejong University, Korea 22  State diagram for random walk mobility model 22 MAP domain consist of rings

23. Network Research Lab. Sejong University, Korea  A ring k is composed of 6k subnets except the ring 0  The number of subnets  If the MN is located in a subnet of ring k  The probability that a movement will result in an increase or decrease in the distance from the center subnet 23

24. Network Research Lab. Sejong University, Korea  Markov chain as the distance between the current location of the MN and center of the domain  The transition probabilities  where q is the probability that a MN stays in the current subnet  The steady state probability 24

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28. Network Research Lab. Sejong University, Korea  HMIPv6 has been proposed to compensate for the problems in employing MIPv6 ◦ but, longer handover latency than MIPv6 when inter-domain handover occurs ◦ load concentration at a particular MAP  This paper proposes MAP changing scheme using VD of HMAP ◦ predictably changes the MAP  May not assure accurate prediction ◦ Reduces overhead generated by complex computation procedure  Performance evaluation ◦ Average number of registration with HA and CN is increased ◦ However, MAP changing scheme reduces inter-domain handover latency ◦ And load concentration of the HMAP is distributed  Future work ◦ How to decide the optimal range of a VD ◦ Simulate the proposed scheme in extended topologies 28

29. Network Research Lab. Sejong University, Korea 29 Thank you for your attention ! Question ?

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