I am formerly from Alvarion.   It sort of is
proprietary.  Especially if you mean the BWA gear
known as BreezeACCESS.  But it stems from the 802.11b
Specificaation for the PHY based on Freq. Hopping. 
This spec you can get from IEEE.org.   It contains the
hopping sequences too.

Cracking it may be hard unless you can sniff the FH
packets from the AP which means getting "Synchronized"
with the hopping pattern of the AP. 
And you cant get 'synchronized' unless you know the
hopping sequence.

There are 26 x 3 = 78 possible hopping sequences.  And
each sequence contains 79 channels in random order.  
And the start time of these sequences is also random.
This makes it hard to even guess the sequence ( even
if you have the sequence,  you're still lost.  You
dont know WHEN the sequence started in time )
Also the 'dwell' time (i.e. how long to stay on a
frequency )can be manipulated too.  The standard is
128 us.   But some FH systems can be set to 64 and 32.

And there's minute amounts of drift.  Assuming you do
get the start time.  Your 'sniffer' has to be able to
correct for 'drift' of the clock in the AP.  Otherwise
over the course of a few minutes to hours you will be
out of sync again with the AP.
  BTW:  the FH systems correct for this drift because
the AP send a 'time code' to the clients causing the
clients to 'update' their internal clocks.

If WEP is used,  (and most of the time it is)  it will
be nearly impossible to keep the sniffer going to
gather enough data to crack the WEP.


As for ready to use tools.  Ask Symbol and/or Raylink.
They still have FH systems too.



=====
Dan Kramarsky
Chief Engineer 
Hayes Wireless Communications, Inc. 

phone: 909-551-7358 
web:  www.hayescomm.com 
e-mail:  dan ATT hayescomm DAHT com

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