Xenofon Vasilakos - xvas@aueb.gr Ph.D. Student at AUEB, MMLab member

1. Proactive Selective Neighbor Cachingfor Enhancing Mobility Support in Information-Centric Networks Xenofon Vasilakos - xvas@aueb.gr Ph.D. Student at AUEB, MMLab member X. Vasilakos, V.A. Siris, G.C. Polyzos and M. Pomonis,

2. Reduce delay experienced after handing off to another location Mobile Users (MUs) in an ICN architecture Running applications with strict delay requirements

3. Receiver-Driven model in ICN Domain A • MU just re-subscribes after completing the handoff Domain B Publisher Publisher ICN architecture

4. ICN is mobile-ready • What about delay after handoff? • Resend request, wait for resolution and path formation • Wait to get data from (another?) publisher • Delay-sensitive applications: • Realtime/emergency notifications, • Teleconferencing, online gaming, etc.. • Sensitive to delay jittering • Multimedia Streaming services Proactive Selective Neighbor Caching

5. Proactive Caching • SNC: Selective Neighbor Caching • Evaluation • Future Work and Conclusion Proactive Selective Neighbor Caching

6. Proactive Caching Publisher • Use proxies • Handle requests • Proactively Cache IOs • Neighboring proxies • One hope ahead Proxy: Cache with mobility support mechanisms J: Set of neighbors Proxy: Cache with mobility support mechanisms

7. Proactive Caching Publisher • Full caching • Proactively fetching and caching requests and IOs to all neighbors • Blind approach • Wastes buffer space • Infeasible to cacheall IOs for all mobiles • Increases delay for other mobiles Proxy: Cache with mobility support mechanisms J: Set of neighbors Proxy: Cache with mobility support mechanisms

8. Proactive Caching • SNC: Selective Neighbor Caching • Evaluation • Future Work and Conclusion Proactive Selective Neighbor Caching

9. Selective Neighbor Caching (SNC) Current Proxy: S: Subset of neighbor proxies i j Mobile User SNC selects only anoptimal subset of neighbors GOAL: Minimize total costs Proactive Selective Neighbor Caching

10. Selective Neighbor Caching (SNC) Current Proxy: i j Mobile User Chit: Delay cost from a selected proxy Proactive Selective Neighbor Caching

11. Selective Neighbor Caching (SNC) Current Proxy: i j Mobile User Chit: Delay cost from a selected proxy Cmiss: Delay cost from a non selected proxy Proactive Selective Neighbor Caching

12. Selective Neighbor Caching (SNC) Current Proxy: i j Mobile User Chit: Delay cost from a selected proxy Cmiss: Delay cost from a non selected proxy Ccache:The cost for allocating buffer space Proactive Selective Neighbor Caching

13. Selective Neighbor Caching (SNC) Current Proxy: i Pij j Mobile User Chit: Delay cost for getting IOs from a selected proxy Cmiss: Delay cost in case next proxy was not selected Ccache:The cost for allocating buffer space Pij:The probability for the MU to move from i and attach to j Proactive Selective Neighbor Caching

14. What is the optimal subset S* ? Discover which minimizes the total cost:

15. Each Proxy decides autonomously Pre-fetching in neighbor jif and only if: SNC is fully distributed and decentralized

16. Proactive Caching • SNC: Selective Neighbor Caching • Evaluation • Future Work and Conclusion Proactive Selective Neighbor Caching

17. Simulation Delay gains over Full Caching

18. Simulation delay gains over No Caching

19. Proactive Caching • SNC: Selective Neighbor Caching • Evaluation • Future work and Conclusion Proactive Selective Neighbor Caching

20. Future work Network topology, multiple levels of proxies Traffic demand, IO size, disconnection period The influence of in-network caching Online cache cost evaluation Consider extensions as discussed in the paper Proactive Selective Neighbor Caching

21. Conclusion • SNC trades-off delay with cache cost • Selects the appropriate subset of proxies which minimizes cost • Simulation investigations quantify cost gains Proactive Selective Neighbor Caching for Enhancing Mobility Support in Information-Centric Networks

22. Proactive Selective Neighbor Caching

23. Analytical Investigations • Assume steady state costs and probabilities • Illustrate the tradeoff: delay Vs. Ccache • how the tradeoff and gains of SNC depend on cost ratios Cmiss/Chit, Ccache/Chit Proactive Selective Neighbor Caching

24. Gain over Full Caching reduces with Cmiss/Chit Gain over No Caching increases with Cmiss/Chit Full Caching No Caching

25. Gain over full caching increaseswith Ccache/Chit Gain over no caching reduces with Ccache/Chit Full Caching No Caching

26. Proactive Selective Neighbor Caching

27. Defining buffer costs Proactive Selective Neighbor Caching

28. Extensions • Identify mobiles of the same type (having a similar mobility behavior) • Consider proxy transition probability for each type • When more than one Musrequest item k • nkis the average number of requests Proactive Selective Neighbor Caching