In a message written on Mon, Nov 08, 2004 at 03:08:13PM -0500, Joe Abley wrote:
I don't know of any applications that require RFC1918 addresses to be deployed. (Clearly, this is not to say there are none.)
By "applications" I did not mean "software programs" but rather "methods of designing networks".
I know of lots of networks that use RFC1918 addresses because of a (perceived, whatever) scarcity of IPv4 addresses, but presumably that argument doesn't necessarily follow for v6 networks, where ever customer site gets a /48.
A company may change providers often and want to use 1918 style space to not have to renumber part of the network, or may choose IPv6 NAT as superior to overlay networks. Indeed, I suspect overlay networks are going to be hugely unpopular.
This sounds like a direct path to IPv6 NAT.
While I do not encourage IPv6 NAT, anyone who thinks IPv6 will put the NAT Genie back in the bottle is smoking some serious crack. Lots of people like NAT for lots of reasons, and I am 100% positive there will be IPv6 NAT used by a lot of people. One obvious use if these proposals pass is to use your non-routable global unique prefix internally and NAT at the borders. Since a lot of people think this is effective security, I think it will be a common configuration.
Perhaps the non-availability of RFC1918 addresses would provide a useful incentive for future v6 network architects to install globally-unique addresses on all hosts? Perhaps I am the only one that thinks that would be a good thing ;-)
Many people share your opinion, and I think it is a good one to voice. That said at the end of the day most engineers are going to treat IPv6 as "IPv4 with bigger addresses". I know most of the IPv6 proponents just wrote me off as a loon by saying that, but I do believe it's reality and you need look no further than the existing test networks to see that it's the case. People who have become used to CIDR, and NAT and such aren't going to forget those idea's because someone told them "rigid boundaries are good" and "you don't need private space anymore". -- Leo Bicknell - bicknell@ufp.org - CCIE 3440 PGP keys at http://www.ufp.org/~bicknell/ Read TMBG List - tmbg-list-request@tmbg.org, www.tmbg.org