Enhancing IP Mobility Handover Management toward Future Internet

1. Enhancing IP Mobility Handover Management toward Future Internet Koshiro Mitsuya Graduate School of Media and Governance, Keio University WIDE Project (InternetCAR, Nautilus proj.) mitsuya@sfc.wide.ad.jp AsiaFI School on Mobile and Wireless Networks

2. Outline • Introduction of new handover concepts • Flow-oriented smooth handover management • Result of the proving test (InternetCAR testbed) AsiaFI School on Mobile and Wireless Networks

3. Background • Deployment of ubiquitous and heterogeneous wireless access networks • Wi-Fi, WiMAX, HSDPA, etc. • Overlapped wireless networks • Multihomed Mobile node • equipped with several network interfaces • switches between or simultaneously uses these interfaces • Proposition • Maximally enhance the end-system to obtain the best possible connectivity in such Multihomed Mobile Internet AsiaFI School on Mobile and Wireless Networks

4. Handover by definition • The process of switching the point of attachment (either L2 or L3) to the Internet appli. appli. Transport IP NIC NIC AP AP AP AR AR AsiaFI School on Mobile and Wireless Networks

5. New Handover Concepts • Per-flow Handover • Each packet determines which path (interface) should be used to transmit the packet • Policy-enabled Handover • The decision is the results of the comparison of the network conditions with user demand • Seamless Handover • The decision dynamically changes due to e.g. the mobility • Switching without service interruption is required • Adaptive Handover • The switching also causes network conditions to change drastically • Some degree of adaptation (e.g. bandwidth smoothing) improves the user experience AsiaFI School on Mobile and Wireless Networks

6. Discussion • Issue 1: Roaming between cell without service interruption (seamless horizontal handover) • IP Mobility (MIPv6, NEMO) • To support traditional applications • Upper layer mobility requires applications to be modified • Problems: delay for L2 handover(A), L3 configuration(B,C,D), and CoA registration(E) AsiaFI School on Mobile and Wireless Networks

7. Discussion (cont.) • + Fast Handovers (FMIPv6) • There are many optimizations (below) but only FMIPv6 optimize (B,C,D) at once • L2 handover, L3 configuration, CoA registration, F-HMIPv6 • Open issue: • We cannot avoid packet loss due to the single CoA limitation • Inter-layer instructions is necessary to perform the fast handover • Link layer information is media dependent AsiaFI School on Mobile and Wireless Networks

8. Discussion (cont..) • Issue 2: Roaming between different network interfaces (per-flow handover and policy-enabled handover) • IP Mobility (MIPv6, NEMO) • MIPv6 only allows to register a single CoA per HoA • It results in the hard handover • Multihoming Extension (MCoA) • Allow to register multiple CoA • No other standard exists • Open Issue: • No mechanism to distribute traffic among available paths • No mechanism to maintain the policy AsiaFI School on Mobile and Wireless Networks

9. Discussion (cont..) • Issue 3: Path switching is happened often due to the mobility, and it causes network condition to change drastically • Network Condition Adaptation can be implemented at several layers • Transport: dynamic renegotiation of connection parameters • Session: RSTP, RTP • Application: bandwidth smoothing, effective compression • Open Issue: • Each optimization technique solves a specific problem so that a combination of several optimizations are required • Each technique independently acquires the link layer info. hence it is hard to integrate them AsiaFI School on Mobile and Wireless Networks

10. Flow-oriented Smooth Handover Management Concept • Separation of Path Maintenance and Flow Distribution • Path Maintenance • IP path establishment • for each interface • API to transparently • use the IP paths • Flow Distribution • Path selection • Flow distribution • Policy management AsiaFI School on Mobile and Wireless Networks

11. Flow-oriented Smooth Handover Management Concept (cont.) • + Handover Services • Defines a set of primitives to assist handover operations • Events (LinkUp, LinkDown, etc.) • Commands (LinkConnect, etc.) • Each protocol solves a specific problem so that a combination of protocols is efficient to maximally enhance the performance • Inter-layer or Inter-node interactions • The standard (abstracted) primitives help the integration AsiaFI School on Mobile and Wireless Networks

12. Example System Flow MNN MR PAR NAR CN Voice+Audio send L2 status update • make a handover decision • decide NAR • make L2/L3 QoS reservation receive NAR info (L2/L3, QoS results) Handover Notification (pre-notification of link characteristics) Fast Handoff(few ms) perform L2 handoff Handover Complete Notification Keep old binding cache for a while Voice only Adapted to the change of bandwidth dynamically & surely AsiaFI School on Mobile and Wireless Networks

13. System Diagram • L2 Abstraction • IP Mobility • MIPv6, NEMO • Optimizations • FMIPv6 (with proposed binding cache mngmnt) • Multiple Care-of Address • Flow Distribution • Adaptive Application • Inter-layer information exchange AsiaFI School on Mobile and Wireless Networks

14. Flow Distribution Policy(draft-mitsuya-monami6-flow-distribution-policy) List of available HoA/CoA pair A HoA/CoA pair AsiaFI School on Mobile and Wireless Networks

15. Example AsiaFI School on Mobile and Wireless Networks

16. L2 Primitives(draft-irtf-mobopts-l2-abstractions) * IEEE802.21 WG refer our works • L2-LinkStatus • Acquisition request for the current link status. • L2-PeerList • Acquisition request for the list of possible access points. • L2-PeerFound / L2-PeerLost • Indication of discovery/missing of candidate access points. • L2-PeerStatus • QoS related information about a peer • L2-LinkUp / L2-LinkDown • Notification that a new link is up / an connected link is down. • L2-LinkStatusUpdate • Notification changes in the status of the connected link. • L2-LinkConnect / L2-LinkDisconnect • Request for connection/disconnection of the specific link. AsiaFI School on Mobile and Wireless Networks

17. New AR HI FNA Previous AR HAck RtSolPr FBU Packets FBack PrRtAdv AP/AR Discovery L3 Handover Preparation L3 Handover L3 L2-PeerList L2-PeerFound/Lost L2-PeerStatus L2-LinkTo BeDown L2-LinkConnect L2-LinkUp Mobile Node L2 Handover L2 Time FMIPv6 (predictive mode)with L2 Primitives AsiaFI School on Mobile and Wireless Networks

18. Horizontal Handover Performance(against G.711 VoIP traffic) 802.11a, WEP, same channel 1 packet lost due to L2 handover 64kbps traffic 80Byte payload packet 10msec AsiaFI School on Mobile and Wireless Networks

19. Vertical Handoverswith L2 Primitives Proposed L2-LinkStatusUpdate-A, (B) L2-LinkStatusUpdate-B, (C ) L2-LinkDown, (D) L2-Connect, (E) L２−LinkDisconnect AsiaFI School on Mobile and Wireless Networks

20. Experiment Testbsd Keio Campus • VoIP clients are communicating via a MR • the MR is equipped with iBurst and EV-DO • the MR will switches from iBurst to EVDO HA DTCP server EVDO W01K In-vehicle MR Mobile Network KDDI/AU Network IPv6 Internet HUB IPv4 Internet SIP server HUB iBurst Network VoIP Client Kyocera R&D Center Log Analyzer iBurst UT • traffic dump • L2 info trace VoIP Client G729(20bytes per 20ms) AsiaFI School on Mobile and Wireless Networks

21. RSSI History and Link Event(Make-After-Break Handover) AsiaFI School on Mobile and Wireless Networks

22. Received VoIP Traffic(Make-After-Break Handover) If there is no inteaction, the performance is just terribule 37s 160s AsiaFI School on Mobile and Wireless Networks

23. RSSI History and Link Event(Make-After-GoinToBreak Handover) AsiaFI School on Mobile and Wireless Networks

24. Received VoIP Traffic (Make-After-GoingToBreak Handover) L2 and L3 configuration takes looong time 16.9s AsiaFI School on Mobile and Wireless Networks

25. RSSI History and Link Event(Make-Before-Break Handover) AsiaFI School on Mobile and Wireless Networks

26. Received VoIP Traffic (Make-Before-Break Handover) • Predictive metho (e.g. pre-configuration) is efficient • Packet loss is still observed because of the phased bandwidth allocation algorithm 350ms AsiaFI School on Mobile and Wireless Networks

27. RSSI History and Link Event(Multihomed Make-Before-Break HO) AsiaFI School on Mobile and Wireless Networks

28. Received VoIP Traffic (Multihomed Make-Before-Break HO) 0ms, no packet loss AsiaFI School on Mobile and Wireless Networks

29. Adaptive Video Conference IEEE802.11b Cellular Changing the video encoding rate dynamically AsiaFI School on Mobile and Wireless Networks

30. Conclusion • Flow-oriented Handover Management + Media Independent Handover Service • Successfully developed the new end-system architecture that enables each application to roam seamlessly and adaptively between ubiquitously deployed networks • Future work • QoS guarantee • Power management AsiaFI School on Mobile and Wireless Networks

31. Thank you for your listening! AsiaFI School on Mobile and Wireless Networks

32. AsiaFI School on Mobile and Wireless Networks

33. Key Contribution • Handover Service • Defined the abstracted link layer events and commands for the persistent IP path maintenance • Defined the abstracted link layer events and commands for the flow migration • FMIPv6 related • Modified the specification on the binding management • Extended FMIPv6 protocol to carry other information needed for handover optimization • Provided the world’s first open source implementation of FMIPv6 • Feedback to the spec, Interoperability tests, Demonstrations AsiaFI School on Mobile and Wireless Networks

34. Key Contribution (cont.) • Flow Distribution • Defined the policy language to describe user demands for the flow distribution • Developed the policy exchange protocol among end and anchor nodes of communications • Network Condition Adaptation • Developed a protocol to share the network condition among end and anchor nodes of communications AsiaFI School on Mobile and Wireless Networks