Re: unmanaged solutions comments

[owens@nysernet.org]

On Thu, 19 Sep 2002, Marc Blanchet wrote:
> automatic tunnels techniques usually mean (by design) that the path is not 
> "controlled".

Perhaps I'm misunderstanding you, but I would expect that any tunnel
between the same two endpoints would follow the same underlying path,
regardless of how it was set up. Everything is driven by the destination
IPv4 address, after all. Unless you have some sort of traffic engineering
going on, but that's always an exception case.
 
And although automatic tunnels don't usually allow you to control the
path, they should select the best possible path based on whatever IPv4
metrics you use, so you probably don't care to be involved ;)

> semi-automatic tunnels techniques like tunnel brokers can be deployed so 
> that it does have less sub-optimal forward/reverse paths. It depends on 
> where/how you deploy them. If they are near to you, network topologically 
> speaking, then the sub-optimal paths might be not that a problem.

I think we're agreeing on the general point that if we use a tunnel
protocol that depends on fixed relays/brokers/servers, having more of them
is better because the odds are that one will be closer to you, and (if the
path is asymmetric, as it is for 6to4 relays) one will also be closer to
the other end. Or are you saying that something else can be done to
improve the situation, without increasing the number of relays?

I am making some underlying assumptions for relays, that they will in some
reasonable fashion connect to the native infrastructure, and further that
the native infrastructure will perform well (though perhaps not as well as
the equivalent IPv4 path). Someone who has a marginal connection to the
'core' of the native IPv6 network (wherever that is) probably won't help
matters by running a relay.

In a semi-utopia, we'd have everyone who is able to connect to the native
IPv6 network doing so, have all our manual tunnels following the best IPv4
paths to the native infrastructure, and have lots of
relays/brokers/servers well connected to both IPv4 and IPv6. I'm working
on all those angles, at least in my little corner of the network ;)

Bill.