TJ wrote: >>> further on the wireless interface. For IPv6, although it receives a >>> huge /64 IPv6 prefix on the wire it can't offer Stateless Autoconfig >>> on the wireless interface. This begs again for IPv6 NAT. >>> >> I'd say it begs for assigning the user a /56 or /48 routed to them on the >> /64 link. >> > > Exactly right! > > A /56 to the home's DHCPv6-PD capable CPE. > (Atleast) one "inside" segment (couple of switch ports, maybe an antenna or > two) for now - sporting SLAAC, maybe Stateless DHCPv6 as well? > A healthy dose of stateful IPv6 firewalling, for those so inclined. > Oh, and probably the same IPv4/NAT/FW we all know and love. > Winner. >
The problem, fundamentally, is one's position in a hierarchy (of IPv6 assignments or pd's). In many markets, there is a (very) limited pool of ISPs (let along ISPs offering IPv6 !!). And, consequently, the ability to ask for and receive something other than a single /64, is limited by the availability of ISPs in the local pool who offer it. It doesn't much matter whether the assignment of a /64 is dynamic or static - either way it bites. There is no guarantee that even a *single* ISP in any particular pool of local ISPs, has enough clue to offer this, or the ability to offer it (regardless of reason underlying the inability). This isn't something I, as a customer, have *direct* control over, and I may not have an alternative (other ISP offering what I want). And it doesn't matter *why*. In such a situation, I am effectively "painted into a corner" (e.g. when viewing IPv6 space as a Heat Map / Hilbert curve). "Bits to the left of me, Bits to the right, Here I am - Stuck in the middle again". (Apologies to the original artist and those who don't like puns.) The question is, what does one do in such a scenario, and/or what *can* one do? If the ability to do what one wants, is permitted by non-64 bit prefixes, life is good. DHCPv6, or more flexible versions of SLAAC, CGA, etc., are needed for this. If only 64-bit prefixes can be used, then one gets only one 64-bit prefix to use for everything. Good luck with that. Basically, in the absence of the ability to subnet arbitrarily (on non-64 bit boundaries), I'm at the mercy of my upstream. 128 bits doesn't look so wonderful in such a scenario, I would surmise. Nobody is a winner. :-( Brian -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
