Hi David， I should answer these questions.
From: David Conrad <[email protected]> Subject: Re: [sig-policy] prop-111-v001: Request-based expansion of IPv6 default allocation size Date: Mon, 27 Jan 2014 22:24:22 -0800 | Hi Guangliang, | | On Jan 27, 2014, at 9:20 PM, Guangliang Pan <[email protected]> wrote: | > I think that statement refers to early IPv6 allocations from the old /23 blocks. Before APNIC received the /12 allocation from IANA, we use sequence allocation method to make /32 allocations and reserved up to /29 for every allocation. That was the practice for all RIRs in the early stage. I believe this policy proposal is trying to address those reserved space. | | That wasn't clear from my reading of the proposal, e.g., the first sentence of the problem statement says: "... while APNIC currently reserves up to /29 for each /32 allocation." I'm sorry for lacking my explation. I'll revise my proposal text about this point. | > Current /32 allocations from the /12 block can grow up to /24 at this stage. | | Err. That suggests APNIC is not using sparse (aka bisection) allocation, rather APNIC now just reserves the the /24 instead of the /29...? I think Guangliang mentioned just about current allocation status with sparse allocation mechanizm described in: http://www.apnic.net/publications/media-library/documents/resource-guidelines/ipv6-guidelines#sparse | In any event, looking at the proposal, I gather there are 3 justifications are provided for a default /29: | | 1) traffic engineering, since some folks out there filter on /32 boundaries; | | 2) potentially fewer prefixes if the ISP needs to expand | | 3) efficiency | | Going in reverse order: | | I don't understand #3. In this context, is the "efficiency" mentioned related to ease of network design? Here I would like to say reserved space which will not use into the future (early IPv6 allocations) can be utilized with this modification. | WRT #2, if I understand correctly, all APNIC allocations for ISPs have sufficient space for that allocation to grow to (at least) a /29 within a single prefix. I don't think APNIC staff would be so silly as to allocate from the reserved/extension space non-contiguously. I did not suppose such non-contiguous case, but there might be a case that LIRs who get additional continuous space announce two /32s not one /31 in order to keep existing network stable. | That leaves #1 which appears to assume the same folks who are currently filtering on longer than /32 won't decide to start filtering on longer than /29. After all, I can easily see the whole point of filtering on /32 by (arguably) overly pedantic network operators as trying to discourage folks from shattering their allocations for traffic engineering purposes to try to limit routing table growth. Once APNIC makes /29 the default allocation size, they could just as easily shorten their prefix filters. Then what, make the default a /24? | | Are there any data on how many ISPs are filtering at /32? I do not have that information, but I observed that I can find some /35s only in part of looking glasses (and prefixes longer than /32 are increasing). Yours Sincerely, -- Tomohiro Fujisaki * sig-policy: APNIC SIG on resource management policy * _______________________________________________ sig-policy mailing list [email protected] http://mailman.apnic.net/mailman/listinfo/sig-policy
