Collab Network Test 0317E

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Revision as of 05:27, 19 March 2008 by Wad (talk | contribs) (New page: This is a forum for discussion about the packet traces obtained in test 0317E. '''Packet Traces:''' [http://xs-dev.laptop.org/mesh/test0317/t0317_E_1.dump Chan 1], [http://xs-dev.laptop.o...)
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This is a forum for discussion about the packet traces obtained in test 0317E.

Packet Traces: Chan 1, Chan 11, Chan 6

Channel 1

Unused Channels

The unused channels (6 and 11) don't have a school server mesh portal point in this test, so they provide a picture of a laptop searching unsuccessfully for a school server.

Taking channel 6, and applying a filter:

wlan.sa == 00:17:c4:11:81:5a

The following behavior is seen on this laptop:

  • We see Beacons sent out at irregular intervals (around 2 - 5 sec)
  • At time 66.85, we see a request for IPv6 RADV (actually two, sent with two different BSS IDs), sent at 2 Mb/s. These continue to appear at roughly every 0.25 sec.
  • At time 67.47, we see the RREQ go out for the first DHCP request. It is sent at four different rates.
  • At 68.615, a RREQ message is relayed for laptop 00:17:c4:0d:37:f5, again at 69.68, 72.69, ...
  • At 68.71 an RREQ for the DHCP server anycast MAC is resent
  • At 71.72, an RREQ for the DHCP server is resent
  • At 72.25, an RREQ is relayed for laptop 00:17:c4:0d:00:01, again at 73.27, ...
  • At 72.54, an RREQ is relayed for laptop 00:17:c4:11:01:f0, again at 74.54, ...
  • At 75.72, an RREQ for the DHCP server is resent
  • Numerous RREQs for other laptops are relayed
  • At 82.72, an RREQ for the DHCP server is resent
  • At 134.61, we see an omen of future problems, as an ARP request from the school server (transmitted on channel 1!) is relayed.
  • Again at 135.99, we see another channel 1 relay, an RREQ from the school server.
  • At 158 sec, we leave this channel for the next one.
  • Overall, roughly 90 seconds were spent on this channel!