Ethereal-users: Re: [Ethereal-users] wifi frame "Supported rates" meaning

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From: Guy Harris <gharris@xxxxxxxxx>
Date: Fri, 11 Nov 2005 01:48:45 -0800
PoWah Wong wrote:
I captured some 802.11 frames with ethereal.
What is the meaning of (B) in "Supported rates"?

To quote ANSI/IEEE Std 802.11, 1999 Edition, section 7.3.2.2 "Supported Rates element":

Within Beacon, Probe Response, Association Response, and Reassociation Response management frames, each supported rate belonging to the BSSBasicRateSet, as defined in 10.3.10.1, is encoded as an octet with the msb (bit 7) set to 1 (e.g., a 1 Mbit/s rate belonging to the BSSBasicRateSet is encoded as X'82'). Rates not belonging to the BSSBasicRateSet are encoded with the msb set to 0 (e.g., a 2 Mbit/s rate not belonging to the BSSBasicRate Set is encoded as X'04'). The msb of each Supported Rate octet in other management frame types is ignored by receiving STAs.

Rates in the BSSBasicRateSet are tagged with (B).

To get copies of 802.x standards online, see

	http://standards.ieee.org/getieee802/index.html