On 6 feb 2009, at 16:02, Joe Loiacono wrote:
Given that ARIN at least is assigning end-user /48s out of 2620::/23 it would be useful to accept these announcements. If not end-user PI is dead in the water. Some providers might like that. End-users probably won't.
That range alone is 25 bits of routing, equivalent to routing all the way down to /25s in the IPv4 world. But I don't see how you could route some /48s without having software to route all /48s and that is hugemongous. And then times 4 for 128 bits. But, I'm not a routing engine guy, so I'm probably missing something ...
The problem is that ARIN reserves a /44 for every /48 they give out. So that means the most you'll see out of that /23 is 2M prefixes (I don't think there are many routers out there that can handle a v6 table this large) but since you need to accept /48s, this could be deaggregated into 32M prefixes. The RIRs need to stop this reservation stuff, it makes prefix length filtering impossible.