Wireshark-dev: Re: [Wireshark-dev] Patch: Prepare for some cleanups of 802.11ad
From: Guy Harris <[email protected]>
Date: Sat, 22 Aug 2015 12:53:29 -0700
On Aug 22, 2015, at 12:17 PM, Richard Sharpe <[email protected]> wrote:

> Hmmm, looking at this again, I wonder if it should not contain an MCS
> field, because the radiotap dissector thinks that mean
> PHDR_802_11_PHY_11N.

Well, *if* there's useful radio information for 802.11ad that isn't provided by the MCS or VHT fields, perhaps there should be a DMG field, containing the radio information for 802.11ad, and 11ad captures should have that field rather than MCS or VHT.

Note that MCS and VHT both include certain fields, so presumably the idea is that an 11ac packet doesn't need both MCS *and* VHT fields.  If there's an DMG field that includes all radio information useful for 11ad, an 11ad capture would only need a DMG field, not an MCS or VHT field, and, for radiotap captures, a packet containing a DMG field could be treated as being an 11ad packet.  (Wireshark should probably warn if a packet contains more than one of MCS, VHT, or DMG.)

Note that the A-MPDU information has a separate field, which could be used in 11n, 11ac, or 11ad frames.