In message <34689.1348009...@turing-police.cc.vt.edu>, valdis.kletni...@vt.edu wri tes: > --==_Exmh_1348009609_2143P > Content-Type: text/plain; charset=us-ascii > > On Tue, 18 Sep 2012 18:18:28 -0400, William Herrin said: > > > In http://lists.arin.net/pipermail/arin-ppml/2010-September/018180.html > > I complained about mapping the full 32-bits of IPv4 address into an > > IPv6 prefix. You responded, "You say that like it's somehow a bad > > thing," and "I'm simply not seeing a problem." > > > > Have you come around to my way of thinking that using 6RD with a full > > 32-bit IPv4 mapping is not such a hot idea? > > They're not in contradiction - you want a /28 so you can do 6RD, ARIN should > let you do that. You want a /28 so you can do a non-6RD network plan, you > should be allowed to do that too. > > But you don't get to deploy 6RD, and then complain that you don't have enough > bits left when you try to do a non-6RD design. > > Or you could be a bit smarter and realize that you probably only actually > *need* > to use 16 or 20 bits of address for 6RD mapping and leave yourself 16 or 12 > for other uses. AS1312 has 2 /16s, so we only need to map 16 bits of address > and one more to indicate which /16 it was and the rest can be implicit. > Which o > f > course still loses if you have more than a /8 or so, or if you have 1,495 > little > prefixes that are scattered all over the /0....
But given that 6rd is DHCP this is all fixed with a little bit of programming. It's not like it's new stuff anyway. It also only has to be done once for each address block. Mark -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: ma...@isc.org
