tcpdump mailing list archives
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. - This is the tcpdump-workers list. Visit https://cod.sandelman.ca/ to unsubscribe.
Current thread:
- Re: 802.11 + radio headers question..., (continued)
- Re: 802.11 + radio headers question... Guy Harris (Apr 13)
- Re: 802.11 + radio headers question... Eddie Harari (Apr 14)
- Re: 802.11 + radio headers question... Mike Kershaw (Apr 14)
- Re: 802.11 + radio headers question... Eddie Harari (Apr 14)
- Re: 802.11 + radio headers question... David Young (Apr 14)
- Re: 802.11 + radio headers question... Guy Harris (Apr 14)
- Re: 802.11 + radio headers question... Mike Kershaw (Apr 14)
- Re: 802.11 + radio headers question... Eddie Harari (Apr 14)
- Re: 802.11 + radio headers question... Guy Harris (Apr 14)
- Re: 802.11 + radio headers question... Guy Harris (Apr 13)
- Re: 802.11 + radio headers question... Guy Harris (Apr 15)
- Re: 802.11 + radio headers question... Eddie Harari (Apr 15)
- Re: 802.11 + radio headers question... Guy Harris (Apr 15)
- Re: 802.11 + radio headers question... Eddie Harari (Apr 16)