Re: An alternative to 6to4 and teredo

[Pekka Savola <pekkas@netcore.fi>]

On Sun, 19 Jan 2003, Erik Nordmark wrote:
> > That's not all.  6to4/Teredo offer an automatic configuration using 
> > anycast addresses.  Much easier than trying to figure out the closest 
> > tunnel broker, configuring to use that etc.
> 
> If somebody wants to provide a good tunnel broker service they can
> automate this without any changes in the clients. 

.. assuming that the protocol TB uses is specified and implemented widely
enough.  Being able to ship it by default in OS's helps.

> Just have multiple tunnel
> servers at different places in the topology and have the tunnel broker
> meaure or estimate the location of the client before handing it
> off to a tunnel server.

.. possibly even requiring specification or at least publication of this 
measument mechanism.

Note: I believe you also need a way to get the list of "tunnel brokers
close to me" -- manually adding them doesn't seem like an option.
 
> Thus if example.net wants to capture IPv6 "customers" that they don't
> have as IPv4 customers they could do this relatively easily.

Assuming above.
 
> > I agree, but there is a cost to a tunnel broker model, that is, not so 
> > simple configuration..
> 
> Yes, but see above. A single icon on the desktop might be sufficient.
> And it has the advantage of lower operational complexity resulting in
> a higher probability that it actually works. And should it not work the icon
> allows you turn turn it off.

Well.. I don't think you can get it much easier than 'echo IPV6TO4INIT=yes
>> /etc/sysconfig/network-scripts/ifcfg-eth0' or the like; that's all you
need to enable 6to4 using the anycast address on certain operating
systems.  No software needed, no nothing: IPv6 in 5 seconds.

Of course "actually works" is relative.

Perhaps, to focus, we should ask ourselves: do we want to provide a
mechanism that provides easy use for the case where:
 1) Joe User wants to use his closest Tunnel Broker that allows him to use
the service (not knowing where this closest TB even is!), or
 2) Joe User digs out the tunnel broker address/hostname of his ISP or 
someone close by and starts to use the service

From my observation point, 6to4 is ultimately superior at 1), at least in
locations where you have some deployment of 6to4 relays (here in Finland,
there are at least two advertising 192.88.99.0/24 and 2002::/16).

Note that to be practical, 1) seems to require that there is some
mechanism of autodiscovering tunnel broker services.  Surfing the web is a
no-go.

-- 
Pekka Savola                 "You each name yourselves king, yet the
Netcore Oy                    kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings