why same names, was Re: NANOG 40 agenda posted

JORDI PALET MARTINEZ jordi.palet at consulintel.es
Wed May 30 21:00:53 UTC 2007

For core networks I will suggest to use pure dual-stack or MPLS/6PE. In the
worst case, if you can't do that, just use manually configured tunnels. For
the upstream, dual-stack or again manually configured tunnels
(6in4/protocol-41 or GRE).

6to4, in general, is useful for end users with a public IPv4 address.

Teredo for those behind NAT.

6to4 and Teredo are already being used by users when their ISPs doesn't
provide any IPv6 service at all.

But they can also be used by ISPs as an easy and low-cost means while they
can't offer dual-stack to the access, by deploying Teredo and 6to4 relays,
in order to improve the availability of IPv6 in their access network w/o any
major cost. As indicated a couple of days ago, I'm starting a thread about
this in AfriNIC (English) and LACNIC (Spanish) in a very few days. I will
drop a message here to remind about that in case people is interested to
follow it (prefer to cross-post in several mail exploders). The thread will
explain how to deploy those protocols and help to resolve any issues. For
Teredo, we will use Miredo, the open source version. For 6to4, as it is
supported in router vendors and hosts, we will explain both of them.

Regarding how many boxes, I think it will be useful just staring with one in
each network and monitor the traffic level. Then you will realize if it make
sense to have more, such as in every PoP, or something similar.

Those protocols work stand-alone, not special operational support required,
and very low cost boxes can make it, at least at this stage.

One more alternative, in terms of next steps planning, for access networks
which can't, at the time being, deploy dual-stack (example DOCSIS 2.0, xDSL
that can't be upgraded yet, etc.), is softwires (L2TP), but I'm not sure
implementations are fully ready yet. I will bet that in 1-2 years, it will
be the best choice and will be able to replace 6to4 and Teredo.

Last, but not least, the major vendor (Microsoft) supports Teredo (as well
as 6to4) in both XP and Vista. In Vista it gets enabled by default when no
native IPv6 connectivity is available, but Microsoft own applications use
Teredo only for peer-to-peer. If no native is present, then 6to4 is the 2nd
choice for client-server apps. This is following the policy table for
source/destination address selection. But other applications may use Terede
as well for client-server. For example Teredo is not used by Internet
Explorer if IPv4 connectivity is available, but if you use Opera, it prefers
Teredo even if IPv4 is available, because is ignoring the policy table. The
policy table can be manually configured. All the information about this is
available at:

About the policy table/XP:

About the policy table/Vista:

About 6to4: http://www.ipv6tf.org/index.php?page=using/connectivity/6to4

About Teredo: http://www.ipv6tf.org/index.php?page=using/connectivity/teredo

LG at: http://www.ipv6tf.org/index.php?page=using/connectivity/looking_glass

Config guides at: 

Hopefully all this is useful.

I'm working in a tool to be able to measure all the IPv6 traffic in a
network, even if it is using Teredo, 6to4, others, so we can realize, in a
few months of measurements (if people different networks is volunteering
fromto use this software and provide data) if IPv6 traffic (all,
peer-to-peer and client-server) is growing. The tool will work EVEN if you
don't support IPv6 in your network, so it will show if some transition
traffic is passing thru.


> De: <michael.dillon at bt.com>
> Responder a: <owner-nanog at merit.edu>
> Fecha: Wed, 30 May 2007 12:41:17 +0100
> Para: <nanog at nanog.org>
> Conversación: why same names, was Re: NANOG 40 agenda posted
> Asunto: RE: why same names, was Re: NANOG 40 agenda posted
>> Before someone starts it, the debate between transition
>> protocols to use is well and truely over. Teredo and 6to4
>> have been chosen for use by the software vendors of the end
>> systems. (fine by me)
> This is misleading. You are using IPv6 jargon (transition protocol)
> whose meaning is not obvious. For most ISPs, "transition" refers to the
> entire series of steps up to running a ubiquitous IPv6 network where
> IPv4 is a legacy support service. In that sense, Teredo and 6to4 are not
> magic bullets because they merely deal with the first steps of such a
> transition.
> I do agree that Teredo and 6to4 are very important right now, as far as
> taking actions, but for planning, we need to look well beyond IPv6
> transition protocols.
> Since we are all collectively playing catchup at this point, it would be
> very useful for some clear guidance on who needs to deploy Teredo and
> 6to4 and where it needs to be deployed. Also, the benefits of deployment
> versus the problems caused by not having it. Should this be in every PoP
> or just somewhere on your network? Are there things that can be measured
> to tell you whether or not lack of Teredo/6to4 is causing user problems?
> --Michael Dillon

The IPv6 Portal: http://www.ipv6tf.org

Bye 6Bone. Hi, IPv6 !

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