wlan channels?

I am familiar with the wireless channels allocation in GSM/GPRS. But
when I am turning to Wlan, I am a little confused about its channels.

1, How many physical channels exist in the specification of
802.11b?
2, When a station is trying to join an ESS, will it listen to all
the channels
for the beacon frame?
3, Can one channel be shared by more than one station? or is it
right at
anytime only one station can send or receive data, although
there are many
channels left(probably negtive).
4, If the wireless channels are arbitraly chosen by stations, what
if a
malacious station keep send and never backoff, so disable all
other
stations?


seems a lot of questions already.

On 10 Oct 2003 12:37:34 -0700, (E-Mail Removed) (Bruce Ding) wrote:

> 1, How many physical channels exist in the specification of
>802.11b?

14 total
http://www.qsl.net/n9zia/dsss-channels.html
http://www.wi-fiplanet.com/tutorials/article.php/972261

note the big overlap of frequency bands of nearby channels. You need
to be 5 channels apart to get minimal overlap.

Phil