On Nov 29, 2007, at 15:43, Lelio Fulgenzi wrote:
I know that having B clients together with G clients brings down the
speed, but is this AP, channel or SSID based?
The Protection feature of 802.11g kicks in on an 802.11b/g AP when the
first "b" station connects. That part only initially affects the
single AP it's on. However, any other APs on that same channel that
can hear the 802.11b station also have to turn on their Protection
since there are "b" stations in range of them. So if your same-channel
APs are close enough together, that single "b" user can impact
multiple APs but only the ones on the same channel it is on.
If I understand it right, the even more annoying case is a if AP#1 has
only "g" users, and AP#2 has a "b" user that AP#1 can't see, if AP#1 &
2 are on the same channel, AP#1 sees AP#2's "b" traffic and also goes
into Protect mode, even though it can't see the "b" user itself. It's
not clear to me if one AP being in Protect mode (but not talking to a
"b" client) triggers the next AP further down the line into Protect or
not.
Regardless, even a single "b" user impacts multiple APs on it's channel.
There's a nice discussion of this in the 2nd edition 802.11 Wireless
Networks O'Reilly book starting around page 300, if you want more
details.
We don't have any intention of turning "b" of in the foreseeable future.
----- Original Message ----- From: "Bruce Curtis" <[EMAIL PROTECTED]
>
To: <[email protected]>
Sent: Wednesday, November 28, 2007 4:27 PM
Subject: Re: [WIRELESS-LAN] 802.11b Support
On Nov 28, 2007, at 10:40 AM, Dennis Xu wrote:
Has anyone stopped supporting 802.11b in your network? Any issues
with that? Got a lots of complains? Thanks!
No, but when we originally enabled WPA2 on a separate SSID we set
the APs to only use 802.11g and 802.11a. The thought was any card
that would do WPA2 would have to be 802.11g capable. However it
turns out that PDAs are slower to support 802.11g and some support
WPA2 even though their card is only 802.11b.
Dennis Xu
Network Analyst(CCS)
University of Guelph
5198244120 x 56217
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Bruce Curtis [EMAIL PROTECTED]
Certified NetAnalyst II 701-231-8527
North Dakota State University
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-debbie
Debbie Fligor, n9dn Network Engineer, CITES, Univ. of Il
email: [EMAIL PROTECTED] <http://www.uiuc.edu/ph/www/fligor>
"My turn." -River
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