Wireshark mailing list archives
Re: Patch: Prepare for some cleanups of 802.11ad
From: Guy Harris <guy () alum mit edu>
Date: Sat, 22 Aug 2015 13:32:07 -0700
On Aug 22, 2015, at 1:09 PM, Richard Sharpe <realrichardsharpe () gmail com> wrote:
Also, I now see that sections 9.7.5a.4 and 9.7.5a.5 imply that MCS headers are appropriate for an 802.11ad capture,
I'm not so sure about that. 802.11ad-2012 has Clause 21, which says: The DMG PHY supports three modulation methods: -- A control modulation using MCS 0 (the control PHY; see 21.4) -- A single carrier (SC) modulation using MCS 1 to MCS 12 (the SC PHY; see 21.6) and MCS 25 to MCS 31 (the low-power SC PHY; see 21.7) -- An OFDM modulation using MCS 13 to MCS 24 (the OFDM PHY; see 21.5) so it has its own MCS values, independent of 11n and 11ac, so there should probably be a DMG field with, among other items, an MCS subfield, containing a value between 0 and 24. Don't be confused by the name of the "MCS" field; it really *should* have been called the "HT" field, as it has subfields for more than just the MCS, and as its MCS values are specific to the High Throughput PHY - i.e., the 11n PHY. The page for it on the radiotap site says: The mcs field indicates the MCS rate index as in IEEE_802.11n-2009. which, if we update it to say "as in Clause 20 of IEEE 802.11-2012", says it has values from 0 to 76, with modulations different from the ones in Clause 21, i.e. the MCS field is *not* appropriate for 11ad.
so the radiotap dissector will need to change to use the frequency set the PHY type.
No, I'd add a DMG field to radiotap, containing, among other values, an mcs subfield, with a Clause 21 MCS value in it. I'm a software engineer, not an electrical engineer, so I'm not even remotely close to an authority on what radio-layer information would be useful, but a quick look at Clause 21 suggests that it might want to include a flag to indicate whether "Static Tone Pairing" or "Dynamic Tone Pairing" was used. ___________________________________________________________________________ Sent via: Wireshark-dev mailing list <wireshark-dev () wireshark org> Archives: https://www.wireshark.org/lists/wireshark-dev Unsubscribe: https://wireshark.org/mailman/options/wireshark-dev mailto:wireshark-dev-request () wireshark org?subject=unsubscribe
Current thread:
- Patch: Prepare for some cleanups of 802.11ad Richard Sharpe (Aug 22)
- Re: Patch: Prepare for some cleanups of 802.11ad Guy Harris (Aug 22)
- Re: Patch: Prepare for some cleanups of 802.11ad Richard Sharpe (Aug 22)
- Re: Patch: Prepare for some cleanups of 802.11ad Richard Sharpe (Aug 22)
- Re: Patch: Prepare for some cleanups of 802.11ad Guy Harris (Aug 22)
- Re: Patch: Prepare for some cleanups of 802.11ad Richard Sharpe (Aug 22)
- Re: Patch: Prepare for some cleanups of 802.11ad Guy Harris (Aug 22)
- Re: Patch: Prepare for some cleanups of 802.11ad Richard Sharpe (Aug 22)
- Re: Patch: Prepare for some cleanups of 802.11ad Guy Harris (Aug 22)
- Re: Patch: Prepare for some cleanups of 802.11ad Guy Harris (Aug 22)
- Re: Patch: Prepare for some cleanups of 802.11ad Guy Harris (Aug 22)
- Re: Patch: Prepare for some cleanups of 802.11ad Richard Sharpe (Aug 22)
- Re: Patch: Prepare for some cleanups of 802.11ad Richard Sharpe (Aug 22)
- Re: Patch: Prepare for some cleanups of 802.11ad Guy Harris (Aug 22)