Eric Louie <elo...@techintegrity.com> writes: > I'm putting together my first IPv6 allocation plan. The general layout: > /48 for customers universally and uniformly > /38 for larger regions on an even (/37) boundary > /39 for smaller regions on an even (/38) boundary
You really really really don't want to subnet on non-nybble boundaries. "Technically feasible" does not equate to "good idea". Optimize for technician brain cells and 2am maintenance windows. Oh, and rDNS. If you can't make your regional aggregation scheme fit within a /32 when rounding up on nybble boundaries... get more from ARIN. Seriously. IPv6 is not scarce. A /32 is the *minimum* initial allocation for an ISP. See ARIN NRPM 6.5.2.1. "justification" is viewed in an entirely different light in the IPv6 land-of-plenty that is IPv6. If you already have a /32 but haven't rolled it out yet, ask for a do-over. "Our subnetting scheme [insert description here] requires a /28" is, at least on paper, an entirely good reason to get a /28 out of ARIN. If you need it and you are having trouble getting it, it's a sign that policy needs further evolution; please reach out to folks involved tightly with the policy process (that would include me) to let us know. As for giving a /48 to every customer... that's a fine way to go and eminently defensible. If every human being on the face of the earth (let's round up and say 2^33 or 8 billion to make it easy) had an end site, and we assume only 10% efficiency in our allocation scheme due to the subnetting scheme I outlined above and getting unlucky... that still uses less than a tenth of a percent of available IPv6 space. This is one of those things that are easiest to get right the first time. If "conservation of address space" is in your IPv6 numbering plan, you're doing it wrong. My $0.02, FWIW. -r
