IPv6

Hi,

I would like to start using IPv6 and A&A seem to know their stuff. If I signed up what would I get in the way of IPv6 addressing?

Will I get a single /64 subnet, or multiple subnets? Would my WAN IP be part of the block I am allocated?

Finally, anyone recommend decent IPv6 capable routers? I currently have a Netgear DGN2000 which I think is now IPv6 capable.

Dave.

AA and others can probably recommend a good IPv6 router for you. I use Linux and have no interest in going the IPv6 router route (excuse the pun).

To answer your other questions, they will delegate you a /48 IPv6 prefix. The IPv6 auto address configuration works on /64 networks only (don't ask why, that's just the way it's done), so on a single connection, you will pick a /64 out of that /48 and use only that. I think they use the remaining /64's for any other broadband connections you might setup on your single AA account eg. you might have a total of 10 lines across the country on one AA account, so you split up the /48 they have delegated you to route 10 individual /64's to each of those lines.

Not much more to say. IPv6 with AA works well, I've experienced no issues with it. Many sites are offering it now - I notice YouTube traffic (for example) is primarily IPv6 now, as Google have migrated most of their platform to it.

In reply to a post by mixt:

The IPv6 auto address configuration works on /64 networks only (don't ask why, that's just the way it's done), so on a single connection, you will pick a /64 out of that /48 and use only that.

Is the WAN IP taken from that /64 block? My current provider gives me a block of 8 (v4) IP's but the WAN of the router is the 1st IP in the block which is bit of a pain, I would much rather a seperate subnet was used on the WAN and LAN side as it makes the router config easier.

It's up to you how you assign your addresses. You can do pretty much anything you want.

I (whether this is right or wrong) have assigned both interfaces eth0 (LAN) and ppp0 (broadband) with the same IPv6 address (the first address of the /48 block they assigned me). Eg. if my prefix is 2001:5:6::/48, I've slapped eth0 and ppp0 with 2001:5:6::

Whilst this works, I've recently ran into some problems with some transparent proxying I'm trying to setup and I think it's because I have put the same address on both interfaces. If you want, you can set the WAN with 2001:5:6:ffff:: and leave the LAN with 2001:5:6:0:: which separates the two addresses and removes any confusion the router may have for having the same address on two interfaces (I may go this route shortly with what I'm trying to do).

Also, I read somewhere about the pros and cons of using the very first available address (2001:5:6:: rather than 2001:5:6::1) - can't remember where I read that now, but I'm sure there is documentation online about it.

FYI, when you enable IPv6 (which is an option that has to be explicitly enabled on Linux PPP setup), AA only assign you link level IPv6 address to your WAN interface - nothing more. See my PPP log below:

Text

1 23 45 6

Nov 19 01:23:09 axis pppd[16794]: CHAP authentication succeeded: BBEU01234567 Nov 19 01:23:09 axis pppd[16794]: CHAP authentication succeededNov 19 01:23:09 axis pppd[16794]: local  IP address 90.155.X.X Nov 19 01:23:09 axis pppd[16794]: remote IP address 81.187.X.XNov 19 01:23:09 axis pppd[16794]: local  LL address fe80::f919:7bf2:5d89:8ff3 Nov 19 01:23:09 axis pppd[16794]: remote LL address fe80::0203:97ff:fe16:c000

These are the addresses assigned (and they change at each PPP login). It is then up to you (as I said above) to configure your interfaces and routing as you wish under the /48 prefix that's routed towards your connection.

Edited by deleted (Tue 20-Nov-12 13:50:14)

You only need the IPv6 subnet "inside" your network, link local addressing will be used on the ppp link to route that traffic to you.
This is one of the nice things about IPv6 where you don't have to waste addresses on transit links.