1 / 27

Inter-session Network Coding in wireless network

Inter-session Network Coding in wireless network. Long Hai 10/02/2012. Outline. Network Coding Intra- and Inter-session Network Coding My Main Work Overhearing Detection for Inter-session Network Coding in Dynamical Network Inter-session Network Coding in Lossy Network.

tamyra
Download Presentation

Inter-session Network Coding in wireless network

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Inter-session Network Coding in wireless network Long Hai 10/02/2012

  2. Outline • Network Coding • Intra- and Inter-session Network Coding • My Main Work • Overhearing Detection for Inter-session Network Coding in Dynamical Network • Inter-session Network Coding in Lossy Network

  3. What is Network Coding? • Network coding is a technique where, instead of simply relaying the packets of information they receive, the nodes of a network will take several packets and combine them together for transmission.

  4. Example1 P1+P2 P1, P2 B1 P1 P2 P3 A B2 2P1+3P2 P1, P2 C P1 P2 P3 P1 P2 P3 B3 P2+3P3 P2, P3

  5. Example2 P1 P2 B A A P1 P2 P1 P1 P1 P2 P1 P2 F P1+P2+P3+P4 P1+P2+P3+P4 P1+P2+P3+P4 P1+P2+P3+P4 B P1+P2 P1+P2 P4 P3 P4 P3 D C P3 C P4 P2 P2 P4 P3

  6. Outline • Network Coding • Intra- and Inter-session Network Coding • My Main Work • Overhearing Detection for Inter-session Network Coding in Dynamical Network • Inter-session Network Coding in Lossy Network

  7. Intra-session Network Coding B1 P1+P3 • The gain of intra-session network coding is from decreasing the retransmission times. (linear coding) 2P1+3P3 A B2 C P1 B3 P1+3P3

  8. B A A P1 F P1+P2+P3+P4 B P1+P2 P1+P2 D C C P2 Inter-session Network Coding • The gain of inter-session network is from reducing the transmitting slots. (xor coding)

  9. P1 is called the SI for D, which is overheard by receivers (D, B) detected by coding nodes (R) Side Information (SI)

  10. Outline • Network Coding • Intra- and Inter-session Network Coding • My Main Work • Overhearing Detection for Inter-session Network Coding in Dynamical Network • Inter-session Network Coding in Lossy Network

  11. The Overhearing Detection (Local vs. Nonlocal) in Dynamical Network • Local Detection: Cope methods (Katti, 2006) • Opportunistic Listening • Learning Neighbor State

  12. Nonlocal Detection • Nonlocal Detection: Dcar method (Jilin Le, 2008) • Routing Overhearing + Learning Neighbor State

  13. Relative Merits of Cope and Dcar • More coding opportunities by Dcar than by Cope • Dcar is not robust.

  14. The SI is piggybacked by every data packet. Dcar: Routing control packet Cope: Report control packet It is a NLD method. more coding opportunities than Cope. more robust than Dcar. Packet Overhearing Detection

  15. An example

  16. Simulation • Two dynamic scenarios: bloat, open

  17. The TPT of dynamic scenarios

  18. Outline • Network Coding • Intra- and Inter-session Network Coding • My Main Work • Overhearing Detection for Inter-session Network Coding in Dynamical Network • Inter-session Network Coding in Lossy Network

  19. Inter-session Network Coding in Lossy Network • Unreliable Overhearing Problem • Irresponsible transmission: no ACK • Free ride: no RTS/CTS • Overhearing Feedback Problem • Periodical report: bandwidth profligacy • Learning neighbor state: UOP

  20. Linear coding • Linear Coding • Xe: output • Xg: input • Kg,e: coding coefficient • Random Linear Coding(Tracey Ho, 2006) • Random coding coefficient • Lemma 1: • On an acyclic network, the successful decoding probability of the network is at least where |F|>δ Full rank

  21. RLC in InteR-session NC (R2NC) • Source: • Unicast • Batch transmission (maybe) • Relay: Coding node • RLC • Multicast • Batch transmission • Destination: Decoding node • Overhearing • Batch feedback

  22. The Characters of R2NC

  23. R n1 n2 The Character of R2NC • For successful decoding: both n1 and n2 have to receive X+Y NC packets. • X+Y: coded packets and overheard packets

  24. The Gain of R2NC • If we set the gain of R2NC as , and let , then • R2NC is not always effective. • The maximal gain of R2NC is related to link state.

  25. A Routing Method Using R2NC Gain (ETX_MG)

  26. Summary • Review of Network Coding • An Overhearing Detection Method for DWN : POD • More feasible for dynamic networks • Inter-session Network Coding in Lossy Networks • R2NC scheme • ETX_MG routing

  27. Thank you for your attention!

More Related