Re: unmanaged solutions comments

[Bill Owens <owens@nysernet.org>]

At 23:33 +0300 9/19/02, Pekka Savola wrote:
> I'd perhaps reword that as "no global tunneled infrastructure".  And even
> then I'd be a bit hesistant: tunneling across short distances is not that
> big a deal, but adding different administrative parties can make it more
> and more difficult.
>
> Solutions like ISATAP can provide rather good performance in a limited
> case;  connections outside of the "site" could be native v6.
That's a good point. I'm thinking of the global IPv6 infrastructure 
and individual hosts or sites connecting to it. And I suspect that 
any solution for this case that uses tunnels, automatic or manual, is 
likely to face the problem of sub-optimal forward and/or reverse 
paths that you mentioned originally. In other words 6to4 is neither 
better nor worse, just different.

As long as the density of tunnels is much less than the density of 
the connections in the underlying network, the path taken by the 
tunneled traffic between two points will be likely to be worse than 
the path taken by native traffic. And the well-known scaling problems 
of tunnels (including crossing administrative domains) makes it 
unlikely that they will become very dense without suffering 
maintainability problems.

Since there are relatively few 6to4 relay routers out there, 
performance is often poor for 6to4 to native traffic. But the same is 
often true for tunnel brokers, and sometimes for manual tunnels. And 
at least 6to4 has good performance to other 6to4 sites.

Bill.