[snip a bunch of stuff where we finally appear to basically agree or at least understand each other]
Actually, that fragmentation was primarily the result of being insufficiently stingy early on.
There are many kinds of fragmentation. When you only get (e.g.,) a v4 /24 for a start, and when you need more, you'll have to get a new non-adjacent /24, there's going to be fragmentation.
I don't think you can equate v4 /24 allocation to v6 /48 allocation. A /48 gives an organization 65,536 unique subnets, each of which can accomodate enough hosts that _EVERY_ IPv4 possible host can have 4+billion addresses. Local policy can move the subnet boundary beyond the /64 point with some effort. Further, every proposal I have made included the concept that an organization with provider independent space smaller than /32 (longer prefix), could only receive at most 1 additional prefix before they surrender their old prefix, and, then, they would only get to keep the old one for a maximum of 24 months to renumber. I believe this removes the fragmentation concern.
We _don't_ want to get to a point where each IPv6 ISP or end-site will have to have dozens of IPv6 prefixes, just because they outgrew the previous ones. There are enough bits to play around.
No, we don't. That's why I've included language in my proposal to specifically prevent this occurrence.
It's not as we are carving out v4 /8's (1/256 of space) for early adopters. Or even /16's. More like the equivalent space of a host address. That's hardly too much. In fact, it's way too little for those ISPs which have home customers like DSL, and it's going to be a a pain because they either must get a new prefix or give their customers a /64 instead of /48.
I think that if an ISP can show that they have more than 65536 home DSL customers, they will not have a problem getting a /31 or larger as needed. However, I think that today, the bulk of DSL ISPs doe not have that many customers and aren't likely to in the near future. In any case, the ones that do already have specific language allowing them to obtain larger prefixes based on the number of end sites they are assigning /48s to, so, I'm not sure why you see that as an issue. Owen -- If it wasn't crypto-signed, it probably didn't come from me.