#10397 NORM Not Tri: XOs may fail to communicate in noisy 802.11 environment

[Zarro Boogs per Child]

#10397: XOs may fail to communicate in noisy 802.11 environment
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           Reporter:  greenfeld  |       Owner:  wad          
               Type:  defect     |      Status:  new          
           Priority:  normal     |   Milestone:  Not Triaged  
          Component:  hardware   |     Version:  not specified
         Resolution:             |    Keywords:               
        Next_action:  never set  |    Verified:  0            
Deployment_affected:             |   Blockedby:               
           Blocking:             |  
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Comment(by Quozl):

 The symptoms you describe are expected in noisy RF environments ... when
 things start to deteriorate, it is mDNS that is likely to be hit first,
 way before TCP, unicast UDP, or ICMP.

 mDNS uses multicast.  multicast is treated differently by access points; a
 lower data rate is used.  As a result, the transmission takes longer, and
 is thus more vulnerable to interference and noise.

 The XOs are quite sensitive; especially with the antennae raised, and so
 they are more likely to receive distant signals at the same time as
 receiving nearby signals.

 You might try with antennae down, or horizontal.

 You might block some of the interference.  Operate the access points and
 laptops below window height, or behind RF barriers.

 It sounds like you have an uncontrolled RF environment.  70 access points
 all operating without any temporal coordination between them will make for
 high probability of interference.

 The persistence in using Salut is incorrect though.  If a Jabber server is
 configured, reachable, and usable, Salut should not be used.  Once Jabber
 is in use, over a TCP connection, the temporal coordination issue becomes
 far less important.

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Ticket URL: <http://dev.laptop.org/ticket/10397#comment:2>
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