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Re: 802.11 + radio headers question...


From: Eddie Harari <eddie.harari () gmail com>
Date: Wed, 15 Apr 2009 14:19:39 -0400

That's true *if* neither the "To DS" nor the "From DS" flag is set in the
packet.  According to "7.2.2 Data frames" in IEEE 802.11-2007:


       if neither "To DS" nor "From DS" are set, Address 1 is the
destination, Address 2 is the source, and Address 3 is the BSSID;


 This is indeed the case of the packets i am sniffing.


For a frame with neither "To DS" nor "From DS", the gap between the
destination address and the IP header would be:

       22 bytes with no QoS, 24 bytes with QoS.

  how come 22 bytes offset with no Qos ?
 in the case both are not set (TO DS and From DS ) then Address 1 is
destination , adress 2 is source  and address 3 is bssid , so there are
18bytes of addresses, then i get the 2 bytes of SEQ control ,  and 8 bytes
of 802.2 and SNAP ,  = 28 bytes ...

 I do know you are correct and i am wrong cause i do see 22 bytes gap. but i
am missing something in the documentation.
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