From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from [10.3.1.93] (helo=sc8-sf-list1-new.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Exim 4.30) id 1FlW0g-0001iK-9a for user-mode-linux-devel@lists.sourceforge.net; Wed, 31 May 2006 12:05:38 -0700 Received: from sc8-sf-mx2-b.sourceforge.net ([10.3.1.92] helo=mail.sourceforge.net) by sc8-sf-list1-new.sourceforge.net with esmtp (Exim 4.43) id 1FlW0g-0000m3-6a for user-mode-linux-devel@lists.sourceforge.net; Wed, 31 May 2006 12:05:38 -0700 Received: from [198.99.130.12] (helo=saraswathi.solana.com) by mail.sourceforge.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.44) id 1FlW0d-0004Ee-DY for user-mode-linux-devel@lists.sourceforge.net; Wed, 31 May 2006 12:05:38 -0700 From: Jeff Dike Subject: Re: [uml-devel] Randomize on MAC address when bringing up ethernet iface Message-ID: <20060531190553.GA6111@ccure.user-mode-linux.org> References: <200605302013.00091.blaisorblade@yahoo.it> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200605302013.00091.blaisorblade@yahoo.it> Sender: user-mode-linux-devel-admin@lists.sourceforge.net Errors-To: user-mode-linux-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Id: The user-mode Linux development list List-Post: List-Help: List-Subscribe: , List-Archive: Date: Wed, 31 May 2006 15:05:53 -0400 To: Blaisorblade Cc: user-mode-linux-devel@lists.sourceforge.net On Tue, May 30, 2006 at 08:12:59PM +0200, Blaisorblade wrote: > I've being thinking to this and I'm wondering why we shouldn't do it. When we > have set no IP or 0.0.0.0, which is not a unique IP, and we bring it up, we > should choose a random MAC to use. > Conditions: the broadcast bit must be 0 and the "locally-assigned address > flag" must be 1 (as likely we already do). Yeah, this sounds like a good idea. > For which bits they are, I've a doubt. > On Tanenbaum's book they're marked as the two most significant (leftmost) bits > (broadcast being the most significant one), but since we've longly known the > broadcast bit is the lowest-order one of the highest bit, I suspect that MACs > are read in little-endian bit order (which likely implies the same for the > whole packets). I can't verify this, but bytes in many fields are moved to be > in network order i.e. big-endian order (MACs are always used in the network > order). So what is the second bit? I only know about the broadcast/multicast bit, and no one has bothered clueing me in on any other special bits :-) Jeff ------------------------------------------------------- All the advantages of Linux Managed Hosting--Without the Cost and Risk! Fully trained technicians. The highest number of Red Hat certifications in the hosting industry. Fanatical Support. Click to learn more http://sel.as-us.falkag.net/sel?cmd=lnk&kid=107521&bid=248729&dat=121642 _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel