Re: Why /64

[Lorenzo Colitti <[e-mail]>]

On Mon, Oct 28, 2013 at 1:10 AM, Jeroen Massar <[e-mail]> wrote:

> The point that I am trying to make, but the one you do not want to hear,
> is that "IPv6 privacy" does not exist


Perhaps, but let's not argue that on this thread, which is about subnet
sizes.


> >     Amongst others: http://www.ipsidixit.net/2010/03/24/239/ one of many
> >     articles on this for free.fr <http://free.fr> (the "largest IPv6
> >     native deployment").
> >
> >
> > Since forever Free.fr has been handing out /60 to all its customers
>
> Hence why the above linked article exists and many other similar ones.
>

The article exists because the writer wanted to put a firewall between the
ISP router and the other machines. You can do that with DHCPv6 PD but not
with native routing (just like you can't do that in IPv4 without NAT). It
doesn't support the assertion that free.fr assigns single IPv6 addresses to
their users.

For free.fr docs on this:

http://ripe58.ripe.net/content/presentations/ipv6-free.pdf (addressing
plan, mentions /60 per user)
http://aide.ma-freebox.fr/ipv6.html (look at the screenshots, they even
allow you to statically route some of your /64s to nexthops you specify)


> IPv6 (this whole thread :) is not limited to a single /128 either, but
> this is how it is being deployed in the wide by various ISPs (cheap
> hosters are a primary example, but there are also consumer ISPs, eg
> Liberty Global mentioned above) who do.
>

Where did you get the information that unitymedia only provide a single
/128? http://www.unitymediakabelbwforum.de/viewtopic.php?f=53&t=23981 and
http://www.youtube.com/watch?v=K0hT1PpfxxQ suggests the CPE gets a /57.


> Note that I am pointing out documentation that is available. That these
> authoritative sources are out of date not much I can do about.
>

Of course you can't do anything about out-of-date documentation, but please
do a little more research before making confident statements based on said
out-of-date documentation. People might believe you, and they'd be wrong.

Specifically, I think the "quite a few [ISPs] give exactly 1 IPv6 address
to their users" statement is not true in the case of mainstream residential
ISPs - I think they all provide at least a /64, and more usually at least a
/60.