Another issue is that certain quad fast ethernet vendors (e.g. Sun) make 4-port cards where each interface has the same MAC address, which would mean I assume that by default each of the subnets run off those ports would have the same /64 network prefix?
The DLink 570TX quad cards we use don't do that, but I think it may be common enough to be an issue? Possibly also revealing vendor equipment in a network by using the MAC address in the prefix is not ideal? My view on stateless autoconfiguration on servers is that it may be a gain in terms of being hidden from port scanning (as opposed to using prefix::1,::2,etc for servers). But if you know the vendor make, the scanning may be down to 2^24 hosts from 2^64 (still a big space), and in a lab of new equipment, the host IDs may be quite close if the network cards came in a batch. Just picking a "random" host part is probably the best compromise; use that 2^64 space :) Tim On Mon, Dec 09, 2002 at 02:10:31PM -0800, Alain Durand wrote: > This proposal is making the assumption that MAC addreses are somehow stable. > I think this is a bad idea. > A simple change of a NIC card in a router will start a renumbering event, > and, although somehow simpler than in IPv4, IPv6 renumbering event are far > from painless. > > On our servers, we recommend not to use staleless autoconfiguration based > on MAC addresses, but instead to use a locally administered token as > interface ID. > Actually, our experience shows that in our environment, IPv4 addresses > are far more stable than MAC addresses. > > - Alain. > > > > by way of Bob Hinden wrote: > > >A New Internet-Draft is available from the on-line Internet-Drafts > >directories. > > > >Title : IPv6 Globally Unique Site-Local Addresses > >Author(s) : R. Hinden > >Filename : draft-hinden-ipv6-global-site-local-00.txt > >Pages : 7 > >Date : 2002-12-6 > > > >This internet draft describes a proposal for IPv6 Globally Unique > >Site-Local Addresses. > > > > > -------------------------------------------------------------------- > IETF IPng Working Group Mailing List > IPng Home Page: http://playground.sun.com/ipng > FTP archive: ftp://playground.sun.com/pub/ipng > Direct all administrative requests to [EMAIL PROTECTED] > -------------------------------------------------------------------- -------------------------------------------------------------------- IETF IPng Working Group Mailing List IPng Home Page: http://playground.sun.com/ipng FTP archive: ftp://playground.sun.com/pub/ipng Direct all administrative requests to [EMAIL PROTECTED] --------------------------------------------------------------------
