Return-path: Received: from mail2.candelatech.com ([208.74.158.173]:39224 "EHLO mail2.candelatech.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729759AbeGRA2K (ORCPT ); Tue, 17 Jul 2018 20:28:10 -0400 Subject: Re: IBSS timeouts To: Nicolas Cavallari , James Prestwood , linux-wireless@vger.kernel.org References: <11bae1aa8b935a170b97650ae61ce236243c1c90.camel@linux.intel.com> <9efa23eb-96e8-12e0-990e-5ee0da62742f@green-communications.fr> <2e189a50-e8f0-0628-4819-27b07b04dd45@green-communications.fr> From: Ben Greear Message-ID: <4038c2b7-314e-d87b-ebb6-48a03c1edcb3@candelatech.com> (sfid-20180718_015312_614799_CF314E9F) Date: Tue, 17 Jul 2018 16:53:07 -0700 MIME-Version: 1.0 In-Reply-To: <2e189a50-e8f0-0628-4819-27b07b04dd45@green-communications.fr> Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 07/17/2018 10:44 AM, Nicolas Cavallari wrote: > On 17/07/2018 17:02, Ben Greear wrote: >> On 07/17/2018 12:57 AM, Nicolas Cavallari wrote: >>> In IBSS mode, all stations are required to send beacons. The protocol >>> is a bit >>> complex to arrange that, every 102.4ms, a station is chosen to emit >>> the beacon. >> >> I'm not sure this part is correct. In practice, it seems to often >> happen this way, >> but last time I read the spec on this it seems like it is supposed to >> sort of negotiate >> and not have all ibss stations beaconning. > > Well, in 802.11-2016, section 11.1.3.5 is clear: "All members of the > IBSS participate in beacon generation." > > On each TBTT, each station must wait for a random delay before > transmitting, and the first one to transmit wins. > > In theory... > See 11.1.3.5, section d and e. I think this means that if it receives a beacon while waiting to transmit one, then it cancels its intent to transmit the beacon. So while they 'participate', they may not actually generate beacons? I could be wrong about my interpretation of this however, and I am not sure how it is actually implemented. Thanks, Ben -- Ben Greear Candela Technologies Inc http://www.candelatech.com