Jim, I can tell you that being forced to implement multiple SP prefixes might be a show-stopper for a numerous of ISPs to implement 6RD, including Swisscom, this is fact. It is a huge operational burden, especially for the IT stack, and means $$$ needed to be spend. So do we want to hamper the v6 rollout because we like to conserve some bits in an almost endless address space? Cheers, Florian 2009/12/1 Jim Reid <jim@rfc1035.com>:
On 1 Dec 2009, at 11:29, Remco van Mook wrote:
If we decide to hand out /24s to 6RD and we think that’s not a waste of address space (even though nobody has been able to give me an satisfactory answer I’m willing to throw in the towel) make that a permanent allocation, not a temporary one. The pretense that people will actually hand back that prefix is, let’s say, not consistent with current experiences in IPv4. Once it’s out of the bag it’s out of the bag, never to return.
Remco, all, I think these two issues should be separated.
You're quite right to underline the absurdity of a policy discussion which is centred around "temporary" allocations. Once the space is given out, it's gone and will never be returned. So I agree wholeheartedly that the policy language should only concern itself with permanent allocations. If there's some other policy that requires temporary allocations for something, then there should be a clear time component to that, like the RIR reclaims the space from the LIR N months after its allocation. Not that that would apply to these 6RD allocations...
As for the mechanics of /24s for 6RD, I'm still confused and uncertain. It's not clear why so much space is needed and if such allocations are wasteful or not. They don't look like an efficient use of address space. Then again, almost no IPv6 allocations can be space-efficient... [For some definition of that term.] My main concerns are how many LIRs will need/want these /24s, the precedents this sets and the impact they have on the overall supply of v6 address space.
I fear we could be treating the abundance of IPv6 space the same way as a lottery winner might spend their money in a bar or casino: a *lot* of fun while it lasts.