A /32 is the minimum for an LIR, but the allocation is made on basis if need, just like in IPv4. Thus if you currently have a million customers then you can justify the need for a million /48s and as such, you end up with a /28 for 20bits and thus 2^20 /48s. Of course you should plan that you will grow in the next few years and that you need aggregation etc, thus you should be able to work out a proper plan like that. You then also understand why there are organisations who got /19s as they are serving countries ;) In the RIPE region it is still the norm to give out /48s. In the ARIN region one can, per policy, choose between /56 and /48 for end-user customers. In general, I would say: - use a /64 to connect the site (::1 is you ::2 is them) - route a /56 to home users, route a /48 to companies Possible good read: Preparing an IPv6 Addressing Plan

I don't have a link (most remeber to make more bookmarks :) ), but I seen to remember that it was an issuu with Tcams running out of space to quickly when allocating less (longer prefix) the a 48. I'll try to find the original document and report back