On Jul 20, 2009, at 10:34 AM, james woodyatt wrote:
On Jul 20, 2009, at 09:07, Iljitsch van Beijnum wrote:Most important issue: "The CPE Router may also support prefix sub-delegation."We should make this a MUST. I don't want to end up in the situation where I get a crappy DSL IPv6 CPE from my ISP and I can't use my own CPE because there is no subdelegation.Careful with that axe... if we're going to require prefix sub- delegation in best-practice CPE routers, then I contend we absolutely need to specify how that's done with zero configuration. Are we ready to do that yet? I don't believe we are. Very happy to be proven wrong about that.
Personally, I am uncomfortable with the topic's treatment in this document.
draft-donley-ipv6-cpe-rtr-use-cases-and-reqs-00.txt and draft-ietf- v6ops-ipv6-cpe-router-00.txt both comment on sub-delegation; the latter tries to specify an algorithm for it. In a document of this type, to my mind, the question is "what RFC MUST/SHOULD/MAY a CPE Router implement", not "what algorithm...". That also reflects the discussion at IETF 74, which recommended dividing the CPE Router Recommendations document into a "2009 recommendations" that would be a working group document and listed RFCs, and a "2010 recommendations" that was an individual submission and requested RFCs on various topics to use in future recommendations. I would be far happier with specifying that
a) a CPE router with one external and multiple internal interfaces that is delegated a prefix shorter than /64 from its upstream SHOULD assign specific /64s from that to its interfaces by an algorithm internal to itself, and
b) It would be Really Nice if the 6man working group designed a multi- router sub-delegation algorithm for cases in which a small network with multiple routers needs to do so within itself.
To me, anything beyond that is not a document making appropriate "recommendations" to vendors regarding their products, or to the likes of CableLabs or BBF regarding the products they deploy.
I don't see an RFC or Internet Draft in any working group that tries to specify sub-delegation for SOHO/SMB networks. Fred Templin has three documents that look at the topic, but to my knowledge they have not been picked up by any working group.