> From: [email protected] [mailto:[email protected]] On Behalf Of > Simon Perreault > Sent: Thursday, January 24, 2013 4:50 AM > To: [email protected] > Subject: Re: RFC6724/RFC3484bis: Destination selection not considering > well-known NAT64 prefix > > From the host's point of view, you don't know that IPv4 is not NATed as > well. You don't even know if it is "native": it could be provided by DS- > Lite for all you know. > > From the operator's point of view, if you deploy a NAT64 in a dual- > stack network, that probably means you *want* traffic to go over > NAT64 rather than over IPv4. You probably want *less* native IPv4 > traffic in your network so that eventually you can make your network > fully IPv6-only.
[WEG] We've been discussing this on and off in sunset4 as well, and I have started to come to the conclusion that it's unlikely that there will be a single correct answer in all cases, and so the better thing is to work toward tools that allow the ISP to give the host some guidance about which address family to choose in different situations, or at least give the host some of the missing information about when something is being NATted or otherwise translated upstream so that it can make its own decision. While any guidance of this nature should be focused on giving the end host the best possible service regardless of the intended destination or protocol, it could take into consideration the costs of different translation models (stateful vs stateless) the absence or presence of a set of ALGs for certain applications, etc. It's still useful to have default recommendations, these would likely be ways to optimize certain scenarios based on specific use cases where it's better to make a different choice than what is recommended in this document. Wes George This E-mail and any of its attachments may contain Time Warner Cable proprietary information, which is privileged, confidential, or subject to copyright belonging to Time Warner Cable. This E-mail is intended solely for the use of the individual or entity to which it is addressed. If you are not the intended recipient of this E-mail, you are hereby notified that any dissemination, distribution, copying, or action taken in relation to the contents of and attachments to this E-mail is strictly prohibited and may be unlawful. If you have received this E-mail in error, please notify the sender immediately and permanently delete the original and any copy of this E-mail and any printout. -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
