ROUTING IPv6

[Bob Fink]

Julio,

At 07:48 PM 5/2/2001 +0000, Julio Aparicio Varela wrote:
>On Wed, 2 May 2001, Bob Fink wrote:
>
> > There is no requirement that folk participating in the 6bone use manually
> > configured tunnelling. At this time there are some (many?) native IPv6
> > links, and also some automatically configured tunnelling using the 6to4
> > mechanism (which isn't under the 6bone space at all as it has its own 
> prefix).
> >
>
>Where can I find those native IPv6 links?

You don't get to know that easily, just as you don't get to know if an ISP 
is using ATM or MPLS or SONET etc.

For the 6bone, it is best to ask the list. But don't get the impression 
there are lots of native paths to choose from, there aren't. I believe 
Japan has many. Our network (ESnet) does IPv6 over ATM.


>6to4, as I have understood, isn't a straight-IPv4-tunneling way?

6to4 is all about tunnelling. From the RFC 3056 "Connection of IPv6 Domains 
via IPv4 Clouds" abstract:

>Abstract
>
>    This memo specifies an optional interim mechanism for IPv6 sites to
>    communicate with each other over the IPv4 network without explicit
>    tunnel setup, and for them to communicate with native IPv6 domains
>    via relay routers.  Effectively it treats the wide area IPv4 network
>    as a unicast point-to-point link layer.  The mechanism is intended as
>    a start-up transition tool used during the period of co-existence of
>    IPv4 and IPv6.  It is not intended as a permanent solution.
>
>    The document defines a method for assigning an interim unique IPv6
>    address prefix to any site that currently has at least one globally
>    unique IPv4 address, and specifies an encapsulation mechanism for
>    transmitting IPv6 packets using such a prefix over the global IPv4
>    network.
>
>    The motivation for this method is to allow isolated IPv6 domains or
>    hosts, attached to an IPv4 network which has no native IPv6 support,
>    to communicate with other such IPv6 domains or hosts with minimal
>    manual configuration, before they can obtain natuve IPv6
>    connectivity.  It incidentally provides an interim globally unique
>    IPv6 address prefix to any site with at least one globally unique
>    IPv4 address, even if combined with an IPv4 Network Address
>    Translator (NAT).


Regards,

Bob