David Young <[EMAIL PROTECTED]> writes:
> I don't think the 802.11 standard concerns itself with merging two
> IBSSs. WECA took up this issue, however, and their interoperability
> standard requires a STA to switch to the oldest IBSS (as indicated by
> the TSF carried by the beacons) with the same SSID on the same channel.
Thanks - that makes a lot of sense.
> I have been able to depend on Prism firmware versions 1.4.9 and 1.5.6
> to do WECA-compliant IBSS merges.
Mine is 1.4.9. Have you seen the 'changing middle two octects"
behavior? Is this a symptom of a 1-member IBSS?
> I have no idea which versions of Lucent firmware do a proper merge.
I had 6.16.1 and 7.28.1. Both seems to have no issues, but I haven't
tried n of each card, etc.
> Note that under the WECA rules, two IBSSs which have formed with the
> same SSID in the same airspace but on different channels do not have
> to merge. Also, a station with a choice of IBSSs with the right SSID
> will usually join the IBSS which sends the loudest beacon or probe
> response instead of the oldest IBSS (the IBSS with greatest TSF).
But then the two IBSSs will be in mutual range, and the merging rules
should require a cascade to the older one.
It sounds like after the merge, if there is a partition, there will
then be two copies of the same IBSS, but each with a separate master
(same BSSID). There could then be TSF drift, and there should be a
new master elected once the partition is healed.
> I doubt that the ADMtek chip does IBSS merges by itself. In my ADMtek
> driver, I have put some rudimentary logic into atw_recv_beacon for
> detecting and joining the oldest IBSS on the channel which has the
> correct SSID. I do not account for Rx and other latencies, yet.
It sounds like this is a host/driver function, which means one could
adjust it to match the spec if it doesn't.
--
Greg Troxel <[EMAIL PROTECTED]>
--
general wireless list, a bawug thing <http://www.bawug.org/>
[un]subscribe: http://lists.bawug.org/mailman/listinfo/wireless
