Return-path: Received: from wx-out-0506.google.com ([66.249.82.234]:5193 "EHLO wx-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752566AbXIVAWZ (ORCPT ); Fri, 21 Sep 2007 20:22:25 -0400 Received: by wx-out-0506.google.com with SMTP id h31so790208wxd for ; Fri, 21 Sep 2007 17:22:23 -0700 (PDT) Date: Fri, 21 Sep 2007 20:23:30 -0400 From: "Luis R. Rodriguez" To: Johannes Berg Cc: Dan Williams , John Linville , linux-wireless@vger.kernel.org, Michael Wu , Daniel Drake , Larry Finger Subject: Re: [PATCH 0/5] Add central regulatory domain agent - Patchset I Message-ID: <20070922002330.GK31768@pogo> References: <20070921204606.GD31768@pogo> <1190410796.14368.17.camel@xo-3E-67-34.localdomain> <1190411390.18521.174.camel@johannes.berg> <43e72e890709211500k741e7a8ai21f2de12eec81926@mail.gmail.com> <43e72e890709211714m312daa6cg8f92c10010d9d8ce@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 In-Reply-To: <43e72e890709211714m312daa6cg8f92c10010d9d8ce@mail.gmail.com> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Fri, Sep 21, 2007 at 08:14:09PM -0400, Luis R. Rodriguez wrote: > http://www.kernel.org/pub/linux/kernel/people/mcgrof/v2-regdomain-pat= ches/ Oh and bellow inline is the Documenation/networking/regdomains.txt I have so far.. its not much but its a start: Luis --- Linux central regulatory domain agent ------------------------------------- The central reg agent consists of two main parts: * ISO3166-1 module (iso3166-1.ko) * Regulatory module (regdomains.ko) Integration with the kernel wireless subsystem is done by extending cfg= 80211 to support a central regulatory domain to which all devices should adhe= re to. Then, mac80211 is expanded to allow devices to indicate their deivice i= s configured to a specific regulatory domain domain, set set either in it= s EEPROM or firmware. Helper routines are also provided for mac80211 to build th= e=20 ieee80211_channel array of hardware supported channels. After a regulatory domain is set all cfg80211 devices are scanned for a= nd their channels are iterated over, only channels which the regulatory do= main indicates are valid for its current regulatory domain are enabled. Powe= r restriction for PtP and PtMP type of connections are also considered=20 and set. Each country can be mapped to one regulatory domain. Each regulatory do= main=20 has two maps for channels, one on the 2.4GHz band and another on the 5G= Hz band. Power restrictions are a little more complicated -- we break both the 2= GHz band and the 5GHz band into 7 logical subbands as follows: Subband name Min (MHz) Max (MHz) IEEE-802.11 Channel range ISM-2.4 2412 2732 1-26 Telec 5005 5145 1-29 UNII-1 5150 5245 30-49 UNII-2 5250 5350 50-70 ETSI 5355 5720 71-144 UNII-3 5725 5825 145-165 AAD 5830 6100 166-220 Note that ETSI also operates on UNII-2, we split this into logical name= s just to be pragmatic. Then for each subband we define specific power restric= tions. The current regualtory map is found in regulatory_map.h A userspace dae= mon can later be provided to update the regulatory map. At the very least the k= ernel should have the world regulatory domain but note that due to large amou= nt of varied restrictions this means only enabling 3 channels on the 2GHz ban= d=20 (5, 6 and 7) and no channels on the 5GHz band with minimal PtMP power restrictions. =46or further implementation details please refer kerneldoc of iso3166-= 1,=20 regdomains, cfg80211, and mac80211.=20 --- Wireles regulatory primer: PtMP - Point to Multipoint PtP - Point to Point EIRP - Equivalent Isotropically Radiated Power IR - Intentional Radiator, transmitter dBm - dB milliwatt (mW), the base says that 1mW =3D 0 dBm dBi - dB relative to isotropic, used to measure antenna gain compared t= o an isotropic antenna on which radiation is distributed uniformly on the surface of a sphere=20 EIRP =3D IR - loss in transmission line + passive gain of the antenna --- Some information based on:=20 http://university.cyberarmy.net/kb/tiki-index.php?page=3DThe+Power+of+8= 02.11 Bellow is an example for FCC. In the 2.4Ghz ISM band the FCC stipulates that the creation of PtMP=20 links be subject to the following restrictions: - EIRP must not exceed 36 dBm (4W) - IR must not exceed 30 dBm (1W) - For every 3 dBi of antenna gain after the first 6 =E2=80=9Cfree=E2=80= =9D dBi the IR must=20 be decreased by 3 dBi (the 1:1 rule) Example (without considering loss) of possible settings if Max EIRP is=20 defined as 36 dBm and we are using the 1:1 rule: TX power (dBm) Antenna Gain (dBi) Max EIRP (dBm) 30-------------------6----------------------36 29-------------------7----------------------36 28-------------------8----------------------36 27-------------------9----------------------36=20 =46or PtP links that rule is augmented: - No Maximum EIRP - IR is limited to 30 dBm (1W) - For every 3 dBi after the first 6 of antenna gain the IR must be=20 decreased by 1 dBi (the 3:1 rule) Example, where IR limit is 30, and has the 3:1 rule above for gain: TX power (dBm) Antenna Gain (dBi) Effective EIRP (dBm) 29-------------------6-----------------------35 30-------------------6-----------------------36 29-------------------9-----------------------38 28-------------------12----------------------40 27-------------------15----------------------42 26-------------------18----------------------44 25-------------------21----------------------46=20 In the 5GHz band the FCC stipulates for PtMP: - UNII-1: Maximum IR power may not exceed 40mW (16dBm) - UNII-1: EIRP may not exceed 160mW (22dBm) - UNII-2: Maximum IR power may not exceed 200mW (23dBm) - UNII-2: EIRP may not exceed 800mW (29dBm) - UNII-3: Maximum IR power may not exceed 800mW (29dBm) - UNII-3: EIRP may not exceed 3.2W (35dBm) - All three bands utilize the 1:1 rule =46or PtP: - UNII-1 Follows the same rules as the PtMP links - UNII-2 Follows the same rules as the PtMP links - UNII-3 May use an antenna with up to 23dBi of gain before the 1:1 rul= e=20 becomes effective. (Giving a maximum EIRP of 200W!!) - To unsubscribe from this list: send the line "unsubscribe linux-wireles= s" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html