From mboxrd@z Thu Jan 1 00:00:00 1970 From: Inaky Perez-Gonzalez Subject: Re: What makes a good fake MAC address? Date: Wed, 22 Apr 2009 15:15:05 -0700 Message-ID: <200904221515.05459.inaky@linux.intel.com> References: <20090423070442.1e643b5b.ipng@69706e6720323030352d30312d31340a.nosense.org> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: Mark Smith Return-path: Received: from mga10.intel.com ([192.55.52.92]:22747 "EHLO fmsmga102.fm.intel.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752369AbZDVWPt (ORCPT ); Wed, 22 Apr 2009 18:15:49 -0400 In-Reply-To: <20090423070442.1e643b5b.ipng@69706e6720323030352d30312d31340a.nosense.org> Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: On Wednesday 22 April 2009, Mark Smith wrote: > Hi Inaky, > > (please CC me, I'm not on the list) > > "The problem with using a zero mac address is that it confuses the > bridging software (and maybe others). I was wondering, what would be a > fake mac address we could put in there that is legal for this kind of > "faking"? [or the closest thing to legal?]" > > Since you're from an organisation with an OUI allocation or two, I > think a real Intel one would be best. It then wouldn't be fake, and no > matter where it was exposed (host only, local network, or globally > e.g. in IPv6 node addresses), it would be guaranteed not to collide > with any other addresses (unless Intel make error an error in their own > OUI administration.) It doesn't really work, because it is for the "from" end of the connection; as said somewhere else in the thread, the WiMAX link is P2P, IP only. The card has a local address, that we use for the "to" field, but for the from, we need to fake an address from the network -- which is not necessarily an intel device :) So maybe local addresses would not be the right choice, and clearly Intel assigned ones neither :) Thanks, -- Inaky