Subject: Re: [rrg] SIP will work fine with CES, CEE won't work with NAT

From: [email-masked] (Noel Chiappa)
Date: Wed, 3 Feb 2010 11:45:15 -0500 (EST)

> From: "Joel M. Halpern" <[email-masked]>

    > definitionally, there really is not that much growth left in IPv4.

Not necessarily; mind, I don't _know_ that there is going to be more growth,
but I can see plausible circumstances where there is continued substantial
growth in the number of routes in the DFZ.

E.g. if some organizations which currently have large chunks of the
globally-visible IPv4 namespace drop back to using smaller chunks of the that
namespace, and the chunks they return are broken up into many smaller pieces
for use by a number of currently non-connected entities.

The exact shape of the future can be awfully hard to predict. If you'd asked
people back in 1995 if we'd be here today, people would probably have gawked
at you... Never say 'Never'... :-)

	Noel

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From: "Joel M. Halpern" <[email-masked]>
Date: Wed, 03 Feb 2010 11:49:39 -0500

I'll readily grant that judgment calls such as I am making are subject 
to the whims of reality.

In fact, if we do not get a reasonable, deployable, usable, multihoming 
and multiconnectivity solution for IPv6, then it won't matter whether 
folks bury v4 in prefixes, or switch to v6.

Conversely, if we do have a good solution, that is less painful than the 
various de-aggregation drivers for IPv4, we have a good shot at moving 
people because the pain is going to be quite high.

I would be happy to see an answer that also helped v4.  But I think that 
is a distinctly secondary consideration.

Yours,
Joel

---

From: Brian E Carpenter <[email-masked]>
Date: Thu, 04 Feb 2010 09:12:37 +1300

> for use by a number of currently non-connected entities.

That is the true unknown for IPv4 - now that we have reached the end game
in prefix allocation, will the resulting food fight recreate a swamp of
a few million tiny prefixes that can't be aggregated?

This is the main reason that my CCR paper says: don't extrapolate the graphs.
We really don't know if the number of prefixes per origin AS will remain
stable or grow signficantly.

> at you... Never say 'Never'... :-)

And yet, they did deploy CIDR, which put us where we are today.

   Brian