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Network Coding Demo for Haggle

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Download java code from http://icawww1.epfl.ch/tmp/NCcode.zip. have Java JDK1.5 installed ... Real traffic. A 5 machine BBN in this room ... – PowerPoint PPT presentation

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Title: Network Coding Demo for Haggle


1
Network Coding Demo for Haggle
  • Alaeddine El Fawal
  • Kave Salamatian
  • Jean-Yves Le Boudec2006 Jan 09

2
Todays presentation
  • Initial feasibility prototype implemented by EPFL
    in Dec 05 and Jan 06 to test network coding for
    Haggle

3
What is Network Coding ?
  • A new paradigm that subsumes routing
  • Well suited for application layer forwarding and
    wireless networking Example A and C talk via B
    used as relay transmission is of broadcast type
    because we are using a wireless LAN
  • Network coding sends a combination of received
    messages instead of repeating them here B sends
    two messages in one transmission

Traditional Method
Network Coding
a
b
A
C
B
a
a
C
A
B
b
b
C
A
B
4
How does it work ?
  • A node makes a random linear combination of
    blocks of incoming packets
  • Using finite field theory easily implemented on
    8 bit processors
  • With high probability, destination can recover n
    packets out of n combinations no coordination
    necessary !

5
Why is Network Coding Well Suited for
Opportunistic Networking ?
  • It can significantly improve probability of
    delivery in a spontaneous network
  • ball in a bin phenomenon time to get all
    messages in a random environment is O(n) with
    network coding, O(n log(n)) with floodingf
  • Example instant messaging Source Philip Chou,
    Microsoft Research
  • Without network coding, use flooding
  • Example Peernet virtual topology with 3 to 7
    nodes as graph
  • Messages flooded to 3 to 7 peers
  • Instead, with network coding, every message
    contains different information
  • Potential gain reduce traffic by a factor 3 to 7
    !
  • Potential incentive for collaboration
  • Nodes are interested in receiving and forwarding
    many packets

6
We implemented Network Coding for Haggle
  • Application supported
  • Distributed bulletin board network
  • One common text file, everyone can append,
    everyone reads everything
  • Does not need any infrastructure
  • No addressing
  • How implemented
  • Messages are network coded with random
    coefficients in GF(28)
  • Every node acts as a digital fountain, sends a
    network coded packet every 100 ms (over UDP)
  • Node stores received info in a file, splits it in
    blocks, network codes the blocks
  • Every packet is a new random combination of the
    data available at this node
  • If no new information received or generated, a
    new random combination of the old (whether new
    info has arrived or not)

7
When Good ?
  • In random, non coordinated, non permanent
    networksAlice leaves the roomnew
    messages are appended during her absenceAlice
    returns to room and gets info back without
    coordination from peers

8
Network Coding for Haggle is Implemented as a
Java Application
  • Implemented in Java
  • Executable over windows, Mac OS, Linux ()
  • Beta version
  • Download java code from http//icawww1.epfl.ch/tmp
    /NCcode.ziphave Java JDK1.5 installed
  • connect manually to network NC Test
  • configure IP address to 10.0.1.x (pick your value
    of x), mask to 255.255.255.0
  • open a shell window in the directory where NC
    test files are locatedand type java
    myApplication C ltmyNodeNamegt

9
Demos
  • Simulation
  • The BBN over a 10 node topology
  • Real application code implemented in Java
  • Topology simulated through Emstar simulation
    environment
  • We show that network coding works without any
    configuration and need fewer redundant packets
    that flooding (ratio is 2 to 3)
  • Real traffic
  • A 5 machine BBN in this room
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