>       All of the WEPs would be created in advance, and entered into the client's 
> configuration
>       and into a database/file which is readable by Freeradius.


Umm.... ICK...  Why go to all that work when you can let the AP's handle
the job of doing WEP key distribution on a much more secure scale??

First of all, you have a misconception.  FreeRadius *DOES NOT* hand out
WEP keys.  That job belongs to the Access Point itself.  At no point
does FR ever know or care to know what WEP key is being used where. 
What FreeRadius does (using the MPPE-SEND-KEY and MPPE-RECEIVE-KEY
attributes) is generate the key that is used by the AP to *encrypt* the
WEP key for delivery to the client.  In other words, though the various
means (TLS, TTLS, PEAP, LEAP), a master key is derived, usually from the
TLS session parameters of the TLS-based methods.  A new key is derived
from the master key on FreeRadius and the client.  FreeRadius then sends
this key through the final EAP_SUCCESS packet to the access point.  The
Access Point uses this key to encrypt the WEP key *IT* has chosed
randomly to the client so that the WEP key is not flying through the air
unencrypted.  The client then uses the master key derived key to
unencrypt the WEP key, install it on the card, and go about its
business.  Most APs also rotate these keys on a regular basis, then use
that same master key derived key to send the new WEP keys to the client.

It is very important to understand this concept when understanding how
EAP and wireless work.

-- 

--Mike

--------------------------------
Michael Griego
Wireless Network Administrator
University of Texas at Dallas



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