The Choice: IPv4 Exhaustion or Transition to IPv6

Thu Jun 28 19:55:25 UTC 2007

On Thu, 28 Jun 2007 12:23:30 -0700
brett watson <brett at the-watsons.org> wrote:

> 
> 
> On Jun 28, 2007, at 11:44 AM, Steven M. Bellovin wrote:
> 
> > Whatever -- it
> > exists as a reasonably stable design; starting over would cost us 15
> > more years that we just don't have.)
> 
> Are you saying we (collectively) would take yet *another* 15 years to
> come up with another and/or better design?

Not so much to design it as to reach this point of maturity.

More precisely, I don't see any reason why it would take significantly
less.  In fact, it can't take much less, no matter what.  Figure two
years for the basic design, 3-5 years for the IETF (or whomever) to
engineer all the pieces (it's more than just the IP header, and until
we have a new design we won't even be able to start identifying the
pieces), 3 years for design/code/test (in the NANOG world, that
includes new ASICs, line cards, etc.), and 3-5 years for much existing
gear (routers, end systems, etc.) to be replaced with the IPvN stuff.
That adds up to 11-15.

I have a lot of confidence in those figures; if anything, I suspect
that I'm being too optimistic.

IPv6 isn't what I wanted it to be (and I was on the IPng directorate).
That said, it's what we have, and I think we *really* need something
with a lot more address space.

		--Steve Bellovin, http://www.cs.columbia.edu/~smb