Return-path: Received: from out2.smtp.messagingengine.com ([66.111.4.26]:40834 "EHLO out2.smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758264AbXHOPYR (ORCPT ); Wed, 15 Aug 2007 11:24:17 -0400 Subject: Re: [PATCHv3] mac80211: dynamic wep From: Volker Braun To: Michael Wu Cc: Linux Wireless In-Reply-To: <200708142355.27708.flamingice@sourmilk.net> References: <1187151162.3253.18.camel@thinkpad> <200708142355.27708.flamingice@sourmilk.net> Content-Type: text/plain Date: Wed, 15 Aug 2007 11:24:15 -0400 Message-Id: <1187191455.6462.14.camel@carrot.hep.upenn.edu> Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Tue, 2007-08-14 at 23:55 -0700, Michael Wu wrote: > I suspect keyidx > 0 is done to allow hardware > without individual WEP key support to continue using hardware WEP. I've wondered for a long time why Cisco chose to use keyidx>0 for WEP unicast keys, but I think I finally understand that this is a weird feature (8.5.1): In a mixed WEP and TKIP network a WEP key[0] would conflict with the TKIP key (which must have keyidx == 0), forcing a dumb TKIP STA to downgrade to WEP. (A good TKIP STA would just rely on per-STA keys and not have this problem) Volker Braun