[agwa]

> Are there any consumer ISPs that do offer customers a block of IPv6 addresses for use, rather than (or as well as) a single IPv4 address?

Comcast, at least in some parts of the country (e.g. SF's East Bay). You don't even have to ask them. One day I noticed my router was being advertised an IPv6 route. I switched on DHCPv6 and got an IPv6 address, as well as a /64 prefix for the rest of my network.

Unfortunately /64 is all you can get for now, which isn't really sufficient, but they've promised to delegate shorter prefixes in the future.

[jerf]

"Unfortunately /64 is all you can get for now, which isn't really sufficient"

Not sufficient for what? (Honest question.)

[agwa]

Sufficient to have more than one subnet. In IPv6 you can't easily have a subnet that's smaller than /64, so even though /64 = 2^64 addresses, it's still just a single subnet. In IPv6, we need to start thinking in terms of number of subnets rather than number of IP addresses.

Why is having one subnet insufficient? I use multiple subnets (I have a guest network), and I don't want to have to use NAT with IPv6 when my ISP has effectively infinite address space. Of course, I'm not an average user, but remember that 10 years ago only power users had home routers, and for everyone else 1 IP address was enough. Now everyone has a router. There are already some consumer access points that tout a "guest network" as a selling point, and there may be other consumer uses for multiple subnets in the future.

[diminoten]

a /65 is a subnet, and you get TWO of them with a /64. And so on. So I don't really understand what you're talking about here.

[agwa]

In theory, you're right. But in practice, IPv6 really wants subnets to be /64. For example, stateless address autoconfiguration requires it.

[diminoten]

It truly is saddening how we're treating v6

[km3k]

I agree. It seems like we're setting up the IPv6 address space to be wasted.

[the_mitsuhiko]

NAT will never disappear.

[agwa]

You're probably right, and one easily preventible reason will be ISPs giving out too-small or dynamic prefix assignments. There may be legitimate reasons for IPv6 NAT, but this isn't one of them.

[zaphoyd]

a /64 gives you a single subnet with effectively infinite size. A shorter prefix would allow you to have multiple subnets for isolating things like gaming devices, guest networks, VPNs, etc. For IPv4 the ability to do this was basically a pipe dream, for IPv6 the addresses are there, we just need to coordinate how ISPs hand them out and how consumer routers manage them.

In short, one /64 is sufficient for duplicating an IPv4 like situation. A /60 or /56 gives us more room to innovate in new types of home networks.

[baq]

yeah, a /64 is more than 2^32 times more than all of current internet... i don't think the GP really meant 'sufficient', or i'm missing something.