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Hi gurus,

Can some tell me the Minimum size of
802.11 Management frame.[For a ACK]

Best

S.Senthilraj

Hi Wizardonwireless@in,

All ACK frames are 14 bytes.

Hi SS of Chennai:

ACK is a control frame. See IEEE 802.11 section 7.2.1.

Frame Control (2) + Duration (2) + Receiver Address (6) + Frame Check Sequence (4) = 14 octets

Management frames carry more information than control frames. See section 7.2.3.

Frame Control (2) + Duration (2) + Destination Address (6) + Source Address (6) + Basic Service Set ID (6) + Sequence Control (2) + Frame Body (0-2312) + Frame Check Sequence (4) = 28-2340 octets

The smallest management frame types, deauthentication and disassociation, each has a 2 octet frame body. Thus the smallest management frame is 30 octets.

I hope this helps. Thanks. /criss

Hi Criss/Devin

I understand now,that the Length of the ACK frame is
14. I went through a Frame capture of 802.11 Autehntication in Page no 340 /342 of CWNA book it
has a Length attribute for the ACK Frame and it says
10.

Is that a bug in the analyzer that you used or iam
still missing something.

Best regards,
S.Senthilraj

Yes, it's a known bug. They forgot to add in the size of the 4 byte FCS. It took about a year to convince all of the protocol analyzer manufacturer's to count the FCS in the frame size for each frame so that it would match the standard. :-)