Return-path: Received: from mail-lb0-f169.google.com ([209.85.217.169]:47740 "EHLO mail-lb0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753083AbaFJVQe convert rfc822-to-8bit (ORCPT ); Tue, 10 Jun 2014 17:16:34 -0400 MIME-Version: 1.0 In-Reply-To: <1402323702.11505.18.camel@umadbro> References: <1401468984-24575-1-git-send-email-rostislav.lisovy@fel.cvut.cz> <1401468984-24575-2-git-send-email-rostislav.lisovy@fel.cvut.cz> <1401825693.4157.44.camel@jlt4.sipsolutions.net> <20140603221837.GU26450@wotan.suse.de> <1402323702.11505.18.camel@umadbro> From: "Luis R. Rodriguez" Date: Tue, 10 Jun 2014 14:16:11 -0700 Message-ID: (sfid-20140610_231650_917648_284535DC) Subject: Re: [RFC 1/4] cfg80211: Add channel flags limiting availability to OCB mode only To: Rostislav Lisovy Cc: Johannes Berg , Liraz Perelmooter , "John W. Linville" , linux-wireless , "linux-kernel@vger.kernel.org" , Michal Sojka , s.sander@nordsys.de, jan-niklas.meier@volkswagen.de, Rostislav Lisovy , "wireless-regdb@lists.infradead.org" , Michael Green Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Mon, Jun 9, 2014 at 7:21 AM, Rostislav Lisovy wrote: > Dear Luis; > Thank you for the introduction in the wireless-regdb mailing-list. > > On Wed, 2014-06-04 at 00:18 +0200, Luis R. Rodriguez wrote: >> Rostislav, can you provide documentation references which would >> clarify >> the stance on 802.11p and restrictions for only allowing OCB mode? > > If I may cite the 802.11-2012 standard: > -- 1st Quote > 4.3.11 STA transmission of data frames outside the context of a BSS > > Communication of data frames when dot11OCBActivated is true might take > place in a frequency band that is dedicated for its use, and such a band > might require licensing depending on the regulatory domain. A STA for > which dot11OCBActivated is true initially transmits and receives on a > channel known in advance, either through regulatory designation or some > other out-of-band communication. > -- End of quote OK the spec does not rule out communication on that special band for regular operation as such that special band is mentioned in the context of OCB communication, but it does say that the frequency range may be licensed. As it stands the public wireless-regdb only covers unlicensed frequency ranges, but it obviously can support licensed frequency ranges, just that the distribution mechanism and integration of the wireless-regdb files then would have to be done separately through separate distributors -- ie, not upstream. If the OCB bands are unlicensed then we can surely add them to wireless-regdb, however it remains unclear if those bands are unlicensed if we can use them for regular non OCB communication. Follow this logic to move forward then: * Poke folks to see if the US band for OCB is licensed or unlicensed * Poke folks to see if the EU band for OCB is licensed or unlicensed * If the bands are licensed then the wireless-regdb changes that would be needed imply that a wireless-regdb needs to be provided to whatever customer by whomever is licensing that entity for usage of that band, that is, we upstream can be removed from the equation of the distribution. The upstream kernel however would require a flag for frequency ranges for OCB frequency ranges. Although the regulatory classes specify a few for the US and EU, this can likely change. I forget if the regulatory class can be interpreted through IEs, if so and if the specification is going to remain static I can envision the ability to hard code the OCB frequency ranges upstream but you'd then need to parse these things. * If the bands are *not licensed* there is one corner case that I still think should be reviewed by regulatory folks: having an OCB frequency range unlicensed under the current reading of the specification of 802.11-2012 means that 802.11 devices *can* use them for OCB, however if OCB is not enabled on the device it seems to be that OCB bands can be used for non OCB communication. Furthermore 4.3.11 seems to be saying that it is only optional to use a dedicated frequency for OCB, OCB can happen on other frequency ranges. > -- 2nd Quote > Annex E (normative) Country elements and operating classes > E.2.3 5.9 GHz band in the United States (5.850–5.925 GHz) > ... > STAs shall have dot11OCBActivated set to true. So all STAs in the US wil have OCB activated? I fail to understand how Annex E should be read in the context of operating classes. > E.2.4 5.9 GHz band in Europe (5.855–5.925 GHz) > STAs shall have dot11OCBActivated set to true. Ditto. Luis