Subject: Re: -current sendmail cancer in IPv4-only kernel
To: Jonathan Stone <jonathan@DSG.Stanford.EDU>
From: Steve Deering <>
List: current-users
Date: 05/08/2000 22:51:50
At 6:48 PM -0700 5/8/00, Jonathan Stone wrote:
>Okay.  *I*, personally, have quite vivid memories of your mentioning
>that IPv6 may not succeed. Quite often.

Yes.  By the way, "may not succeed" is not quite the same as "may never
be deployed", which is what you originally quoted me as saying.

> I guess I recall that more vividy than the qualifications.

So it seems.  

>I've never said that NetBSD should not include IPv6, or not ship it.

OK, as I said, I have not been following this mailing list, so I probably
over-reacted based on a misunderstanding of what was being proposed.
I read your message as a plea to keep NetBSD "IPv6-free" based on
bogus claims about IPv6's "undeployability" and unsubstantiated allusions
to "real technical questions" about it.  The fog of disinformation made
it hard for me to clearly see what you were actually asking for.

> >If people were proposing to remove support for IPv4, I could appreciate
> >your unhappiness, but that doesn't appear to be the case.
>Steve, the suggestion to drop support for IPv6-less kernels is
>precisely what I objected to,...

No, when I said "remove support for IPv4", I was using hyperbole and
was referring to deleting IPv4 altogether.  If people were proposing to
do *that*, then I said I could appreciate your unhappiness (which was
meant to be understood as understatement).

>Besides, I think what you say below says your estimate has changed
>since last time I heard you give it. Fair comment?

Yes, my estimate of the odds of success has increased.

>again, All NetBSD binary distributions and snapshots ship with IPv6
>support in both kernel and userland.  The scenarios that've made me
>unhappy have been where I build my own v6-free kernels, and the NetBSD
>precopiled userland code doesn't deal with that as gracefully as it

OK, it sounds like this is being remedied.

> >I don't doubt it.  Interestingly (to me), I have gone through the opposite
> >evolution, starting off quite pessimistic, and getting more and more
> >optimistic as the data comes in.  I guess the people you've been talking
> >to have a different source of data, or draw their conclusions based on
> >something other than data.
>Interesting. Do you mean data on early deployment rates, or data on
>people who've looked at IPv6 and decided not to deploy it?

I meant data on the number and status of implementations of IPv6, the
success of early deployments (especially in Japan), the small but growing
number of ISPs who are actively deploying IPv6, the good match of IPv6
(and the poor match of IPv4) to the needs of the next-generation cellular
phone networks and the demonstrated ability of that industry to rapidly
deploy very large-scale, Internet-interoperable networks based on
something other than IPv4 (e.g., WAP), and the number of knowledgeable
and influential people who were previously opposed to, or non-committal
towards, IPv6 who have recently come out in support of IPv6 because
they have realized that the problems with IPv4 are serious and that IPv6,
regardless of its imperfections, is the best hope we have to address
them (no pun intended).  That sort of data.