On Fri, Sep 27, 2013 at 02:10:47AM -0400, Ryan McIntosh wrote:
I don't respond to many of these threads but I have to say I've contested this one too only to have to beaten into my head that a /64 is "appropriate".. it still hasn't stuck, but unfortunately rfc's for other protocols depend on the blocks to now be a /64..
I became a "convert" to the school of thought that hands out a /48 to every end user when I realised that the current, *most* profligate addressing scheme anyone's recommending involves essentially giving out an IPv6 /48 to anyone who's currently getting an IPv4 /32 (eyeball SP end-users, and dedicated server / VPS customers). Even with this scheme, we have an address space over eight *thousand* times greater than what we have now[1]. If I am the current IPv4 Internet, then we can have more IPv6 Internets than there are people in the town I live in. Once that sunk in, I realised that, practically speaking, we're solid. Yes, there have been a few "big" blocks like /20s handed out, but they're few and far between. I work for a comparatively *tiny* hosting company, and we've got 3 IPv4 /20s, and yet the single IPv6 /32 we've got should more than do us for a *very* long time to come[2]. I'm now firmly in the camp that the resource to be worrying about is routing table slots, not address space exhaustion.
It's a waste, even if we're "planning for the future", no one house needs a /64 sitting on their lan.. or at least none I can sensibly think of o_O.
I prefer to think of it as simply "enough address space I don't have to worry about manual assignment", rather than "I'm 'wasting' 18446744073709551612 addresses". Thinking of IPv6 as being a 48-bit or 64-bit address space that also has the added bonus of never having to worry about host addressing makes things a lot more palatable. - Matt [1] And that's assuming that we only use 2000::/3 for this go around, which is one of six /3 blocks that we have to play with. If we completely fuck this up, we've effectively got IPv's 7 through 11 to try different ideas without having to change addressing formats. [2] To be fair, we're using an IPv6 addressing scheme that involves a lot more compaction than "/48s for everyone!", but even if we were handing out /48s for every machine in our facilities (which we wouldn't need to do, because plenty of customers have multiple machines, and thus would get a single /48 for all their machines), we'd still not be running out any time soon -- we've got ~65k IPv6 /48s, compared to ~12k IPv4 /32s, so yeah... -- Generally the folk who love the environment in vague, frilly ways are at odds with folk who love the environment next to the mashed potatoes. -- Anthony de Boer, in a place that does not exist