#6211 BLOC Future : patch for support of per packet mesh ttl

[Zarro Boogs per Child]

#6211: patch for support of per packet mesh ttl
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  Reporter:  mbletsas     |       Owner:  dwmw2                         
      Type:  enhancement  |      Status:  new                           
  Priority:  blocker      |   Milestone:  Future Release                
 Component:  wireless     |     Version:                                
Resolution:               |    Keywords:  libertas, ttl, mesh, Update.1?
  Verified:  0            |    Blocking:                                
 Blockedby:               |  
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Comment(by mbletsas):

 Assume that you have a simple "chain" mesh config A<->B<->C
 If you set the multicast TTL to 1, then A will never find out about C and
 vice versa (with the existing Avahi scheme).

 Setting the multicast mesh TTL to 1 helps is fully connected instances
 like the ones you get in a classroom where each laptop directly
 communicates with every other laptop.

  A - B
   \ /
    C

 In this scenario every multicast frame originating in A will have to be
 retransmitted
 by B and C concurrently, which will create contention. Setting the mesh
 ttl to 1, alleviates that issue.

 That setting should be easily enabled and disabled (together with
 multicast rate and mesh path expiration) when you *have* to use the mesh
 in such a situation.
 It is by no means something that you want to hardcode anywhere

 M.

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Ticket URL: <http://dev.laptop.org/ticket/6211#comment:9>
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