> The short answer is, "I don't know" because I don't have your data, but what
> assumptions did your modeling make about adjacent channel rejection figures
> and CCA thresholds on the clients?

I wish I had those particular numbers myself - I've looked but didn't
come out of that employment with them.  As Ron noted, the
adjacent-channel philosophy started with Cisco recommendations.  As
switch jockeys are wont to do, the APs were typically configured at 50
and 100mW with 3-12dBi antennas, and channels were not always selected
to be non-adjacent (the less-wireless networking guys set up the first
pass at coverage).  Coverage was horrible and the nine of us spent an
inordinate amount of our time troubleshooting what ended up being
coverage issues.  After what seemed to be careful modeling (lots of
highly-mobile clients & steel like Ron noted as well) and analysis, we
settled on 30mW + 3dBi on 120' centers.  This gave us largely -67 to
-72dBm client coverage on 802.11b - that was with mostly Orinoco-based
(later Atheros) cards.

Now that I look back at it, I don't think anyone really even
questioned whether "channelization" was right.  Roaming between cells
was rapid and throughput for clients remained high without much jitter
(VoIP toward the end) - we didn't seem to have reason to test any
other configuration.

Regardless, I really do appreciate your taking the time to explain
further - as is normal, I get to thinking I understand a technology,
then someone shows me how little I really do know.  First glance tells
me I likely have nothing to add or respond to on your other two
emails.


RB

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