From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from nbd.name ([88.198.39.176]:56059 "EHLO ds10.nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753837Ab0D0BmZ (ORCPT ); Mon, 26 Apr 2010 21:42:25 -0400 Message-ID: <4BD640F5.8010206@openwrt.org> Date: Tue, 27 Apr 2010 03:42:13 +0200 From: Felix Fietkau MIME-Version: 1.0 To: "Luis R. Rodriguez" CC: "John W. Linville" , Jouni Malinen , linux-wireless@vger.kernel.org, johannes@sipsolutions.net Subject: Re: [PATCH 1/2] cfg80211: add ap isolation support References: <1272324216-73349-1-git-send-email-nbd@openwrt.org> <20100426232332.GA2079@tuxdriver.com> <4BD621FA.1000405@openwrt.org> <20100427001233.GB2079@tuxdriver.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On 2010-04-27 3:34 AM, Luis R. Rodriguez wrote: > On Mon, Apr 26, 2010 at 5:25 PM, Luis R. Rodriguez wrote: >> On Mon, Apr 26, 2010 at 5:12 PM, John W. Linville >> wrote: >>> On Tue, Apr 27, 2010 at 01:30:02AM +0200, Felix Fietkau wrote: >>>> On 2010-04-27 1:23 AM, John W. Linville wrote: >>>> > On Tue, Apr 27, 2010 at 01:23:35AM +0200, Felix Fietkau wrote: >>>> >> This is used to configure APs to not bridge traffic between connected stations. >>>> >> >>>> >> Signed-off-by: Felix Fietkau >>>> > >>>> > Is this useful? >>>> Yes, if you have an AP with lots of users that aren't expected to >>>> communicate with each other (e.g. only for internet access), it can save >>>> a lot of airtime by not forwarding every broadcast message emitted from >>>> any station. >>>> I'm sure there are a more situations where this can be useful. >>> >>> Ah, OK -- I suppose that makes sense. >> >> In fact technically IEEE-802.11 2007 section 11.7 states "STAs are not >> allowed to transmit frames directly to other STAs in a BSS and should >> always rely >> on the AP for the delivery of the frames", with the exception being >> using DLS direct links for QoS STAs. This would prevent the STAs from >> going into PS mode for as long duration of the stream. >> >> If the AP does not support this it would just set the result code for >> DLS requests to "Not allowed in the BSS". It does not seem the >> standard has a way for an AP to teardown an existing DLS links though >> (at no reason code for it), so I guess if we ever support DLS we won't >> be able to enable this option if a direct links is already >> established. > > Now that I think about it, why is this even required, why not just > enforce this all the time and have an option to disable DLS? Are there > ways to enable direct STA <--> STA communication on a BSS other than > DLS? I think allowing/disallowing DLS should be separate from AP isolation. In some cases, AP isolation might only be used to reduce the amount of broadcast traffic, and DLS wouldn't be a problem then. - Felix