Return-path: Received: from mail-px0-f103.google.com ([209.85.216.103]:39292 "EHLO mail-px0-f103.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752620AbZEVSgA (ORCPT ); Fri, 22 May 2009 14:36:00 -0400 Received: by pxi1 with SMTP id 1so1477303pxi.33 for ; Fri, 22 May 2009 11:36:02 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <40f31dec0905220646r4dd2fb0ag1e683ae95aab810b@mail.gmail.com> References: <40f31dec0905220646r4dd2fb0ag1e683ae95aab810b@mail.gmail.com> From: "Luis R. Rodriguez" Date: Fri, 22 May 2009 11:35:42 -0700 Message-ID: <43e72e890905221135v2520c9f1o5c41eb30f4de8913@mail.gmail.com> Subject: Re: mac80211: TDMA approach feasible? To: Nick Kossifidis Cc: ffileppo , "kalle.valo" , linux-wireless , Michael Green Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Fri, May 22, 2009 at 6:46 AM, Nick Kossifidis wrote: > 2009/5/22 ffileppo : >> >>> > I was wondering if with mac80211 is now possible (and what effort is >>> > needed) to implement a TDMA approach. In particular I would like to: >>> > override 802.11 MPDU frame format, eliminate RTS/CTS exchange, >>> > eliminate automatic ACK and retransmission, eliminate virtual carrier >>> > sense (NAV), control PHY clear channel assessment and control >>> > transmission backoff. >>> >>> Most of this is usually implemented in firmware, so you need access to >>> firmware sources. >>> >> >> Hi, >> thanks for your answer. >> >> If these features are implemented in firmware, it should be possible to modify them if using for example Ath5k (which is a completely FOSS Linux driver) Right? Could you give me any directions? >> >> Talking about the TDMA implementation I was wondering if it is possible to achieve a time granularity of 1?s using commercial-of-the-shelf wifi cards (e.g. atheros ones). >> >> I would appreciate any ideas or thoughts on this matter. >> >> Thank you, >> >> Francesco >> > > Check out freebsd they have TDMA support for the ath driver as far as > i know. It would be cool if we could port it on linux ;-) And if such support comes around, it would make sense as a separate driver. You would need also need a way to ensure proper regulatory compliance. http://wireless.kernel.org/en/developers/Regulatory CRDA was designed to be flexible for any wireless technology. Luis