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[802SEC] Dominance allegation in 802.11 TGax

Dear 802.11 participants,


I have received an allegation of dominance in 802.11 TGax,  so shown below,  and posted at:



From Graham Smith, 2016-06-16:


I thank Adrian for presentation of the slides pertaining to dominance presented at the May 2016 midweek plenary. As a result of reading these slides I am convinced that I have been actively discriminated against in TGax. I can only describe this by citing the actual example as experienced by me, and I realize that this can get somewhat complicated, but I do not know how else to describe my experience. 

I have been presenting my ideas on “Dynamic Sensitivity Control” (DSC) for over 2 ½  years (first presented Oct 2013 in WNG), with detailed calculations, analysis and technical discussions, based upon the set 11ax scenarios, with over 14 individual submissions (plus revisions) and in the order of 30 other presentations related to DSC including several independent (i.e. not from companies working as a consortium in a SIG) simulations. I believe that DSC has had more analysis than any other spatial reuse scheme, and it has been shown that it does provide for spatial reuse in a superior manner.

In the spatial reuse ad-hoc group in particular, but also in the TG, every straw poll by me has been voted down:

May 2015 “The amendment shall include one or more mechanisms to improve spatial re-use by adjustment of the sensitivity and/or CCA threshold levels.”

Failed 17/6


July 2015 “The amendment shall include one or more mechanisms to improve frequency re-use by adjustment of the sensitivity and/or CCA threshold level(s).”

Failed 19/9


In fact the Spatial Reuse ad-hoc group had no entries in the SFD until September 2015, having refused to agree to these quite benign polls.


Then in September, we had a presentation by 108 authors from 16 affiliations on “Adaptive CCA and TPC”.  The proposed wording for the SFD “Valid OBSS PPDU as not being received at all…if the RXPWR…is below the OBSS_PD threshold and TBD conditions are met, noting that the OBSS_PD threshold is accompanied by a TXPWR value and a reduction in the TXPWR may be accompanied by a TBD increase in the OBSS_PD threshold value.” – Passed 38/1

So coupling DSC, but disguised as OBSS_PD, with TPC (transmit power control) instantly gets accepted on the basis of one presentation.  Note that TPC only works, of course, if the OBSS network also does it (a later presentation by me showed TPC has further problems unless the OBSS AP also reduces power, a difficult concept).


Similarly in September we had a presentation by 101 authors from 15 affiliations on ignoring “inter BSS PPDU… below an OBSS PD level” - Passed 39/0.  Astonishing result considering the amount of work presented (compared to the DSC work).  This concept is related to the use of “color” which, similar to TPC, must be used by all STAs and AP in the OBSS for it to be of any use (yes I know it is proposed for 11ah, but that is a closed PHY).  Immediately accepted, of course, on the basis of one presentation.


Then also in September 2015 a proposal, this time by 1 author from 1 affiliation (not me), to simplify the requirement “The amendment shall include one or more mechanisms to improve spatial reuse by allowing adjustments to one or more of the CCA-ED , CCA Signal Detect , OBSS_PD or TXPWR threshold values. The constraints on selecting threshold values are TBD.

Passed 24/0.  How this gets accepted when my earlier ones did not is strange, but, at last DSC seems to be allowed.

At the March meeting a presentation by 126 authors from 18 affiliations sets out some strict formulas on the OBSS_PD and TXPWR settings, but still with TBDs and no actual description on how to do it in practice, passes 22/1. 


Now, reaching out to several members with affiliations to companies within the SIG, they confirm that DSC appears to be covered, so I write a presentation investigating and analyzing DSC, Color and TPC, and write full text for DSC.  These I first present in a teleconference, and then formally at the May meeting. After the presentation of an independent detailed DSC simulation that showed very positive results, I try a simple poll:

Text describing DSC may be considered for inclusion into the 11ax amendment.” Failed 2/1/many.


I am convinced that I have been subjected to deliberate exclusion, that my presentations have not been taken on merit, and I believe that a block of members have deliberately agreed among themselves to exclude my idea. Similar proposals, with much less analysis or description and with higher levels of complication and introduced about 18 months after DSC was first described in detail, pass with big margins.  I therefore can only conclude that this is due to the companies working together in the SIG in TGax which has exercised its influence by reason of superior leverage, strength, and representation to the exclusion of fair and equitable consideration of other viewpoints, and in particular, mine.




I will be consulting during the July session with the IEEE 802 chair, Paul Nikolich,  and the executive committee (EC) members on how

to respond.


Yours sincerely,


Adrian P STEPHENS (Dr)

Chair, IEEE 802.11 Working Group

Senior Principal Engineer,  Intel Corporation


Tel: +44 (1793) 404825 (office)


Intel Corporation (UK) Limited
Registered No. 1134945 (England)
Registered Office: Pipers Way, Swindon SN3 1RJ
VAT No: 860 2173 47


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