[135595] in North American Network Operators' Group
Re: Another v6 question
daemon@ATHENA.MIT.EDU (Owen DeLong)
Thu Jan 27 01:35:04 2011
From: Owen DeLong <owen@delong.com>
In-Reply-To: <AANLkTi=fJbDuv1X_cDSWMzAF7sBkF+2K7+eso97NiQBc@mail.gmail.com>
Date: Wed, 26 Jan 2011 22:29:30 -0800
To: Max Pierson <nmaxpierson@gmail.com>
Cc: nanog group <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Jan 26, 2011, at 9:31 PM, Max Pierson wrote:
> >V4 30 years ago -- expected consumption: ~60 /8s of 256.
> >IPv6 today -- expected consumption: Maybe 15 /12s of 4096.
> >The scales in question are vastly different.
>=20
> I made no such comparison between the two. The scales are vastly =
different, but I think you're still missing my point. 30 years ago, no =
one "expected" cells phones to consume IP's. 30 years ago, no one =
"expected" xbox's and playstations to consume IP's. Point being is the =
"unexpected".
>=20
I'm not missing your point. I'm saying that in IPv6, we've put enough =
addresses
in to allow for things nobody has thought of in 30, 60, 90, even 100 =
years and
then some.
> >Not at all... In my opinion, IPv6 will probably last about 30-50 =
years. In my opinion, IPv6 addressing will outlast IPv6 usability on =
other fronts. I >absolutely think we'll have to do this all again. I =
just don't think that addresses are going to be the thing we run out of =
next time.
>=20
> Ok then, what is it exactly you think we'll run out of in 30-50 =
years?? Please elaborate.
>=20
If I knew, then, I'd be well on my way to much greater wealth. Whatever =
it is, I am only
certain of the following things about it:
1. We have no idea what the requirements will be at this =
time.
2. We have no idea which particular scaling limit in IPv6 =
will actually drive
us to the next protocol.
3. Our needs in 30-50 years will be different than our =
needs today.
4. This all assumes that we have a human race to care about =
having an
internet in 50 years. Such is not necessarily a safe =
assumption.
> >No, that's not what I said at all. What I said was that addressing =
isn't going to be the constraint that causes us to have to revamp it =
next time.
>=20
> Once again, please elaborate.
>=20
See below... I pretty much did elaborate in another message about
the number of /48s and the construction rate required to consume
them.. I don't know what will cause us to
revamp it next time. I'm just sure there are enough numbers to make
it to that point.
> >The point was that if you're trying to figure out how big routers are
> >going to have to be for near-term IPv6 or even medium-term IPv6
> >deployment, counting the total possible number of prefixes isn't
> >a useful metric because the actual utilization will be nowhere
> >near that large and the numbers are impossible to use as an
> >engineering spec. for any technology yet known.
>=20
> Actually, my original post may have been somewhat misleading due to =
"what a global table would look like in say 3 or 5 years after v4 is =
exhausted" and "in our routers just to take a full table". I wasn't =
referring to just v6 deployment moving forward. I didn't mean after v4 =
goes away completely. I was adding v4 table + v6 table (assuming we =
dual-stack, if you separate the two, ~4000 prefixes fit quite nicely on =
just about anything still running today, and that also makes the second =
question of my original post irrelevant). We won't need that amount of =
memory after v4 goes away (probably for quite some time). The prefix =
count at that point will be significantly lower. I understand that. =
Apologies for not being clearer.
>=20
Well, once IPv6 is more fully deployed, you'll be seeing at least 30,000 =
and more like 75,000 prefixes in IPv6. That's because there are about =
30,000 active ASNs today and given tendencies towards traffic =
engineering, greater multihoming, easier address acquisition and some =
other factors, a 2+ growth factor over ASNs wouldn't surprise me in the =
short term.
> >I'd like to see IPv4 go away in ~3 years. Any faster would be too =
traumatic.
> >I think 6 years is a perfectly reasonable time frame. I think if it =
takes 11 years
> >it will be because of significant foot-dragging by some key =
organizations.
> >I'm not convinced that foot-dragging is as likely as some people are, =
but,
> >there's enough probability to provide some wiggle room in the =
numbers.
>=20
> I agree, although I do think there will be some foot-dragging, I just =
don't think it will take 11 years. If anyone at that point is still =
speaking only v4, IMO they'll only be speaking to "127.0.0.1".
>=20
I think there will be quite a bit of foot dragging. I think you =
misunderstand me.
I'm expecting everyone to be pretty much dual-stacked in the next 3-4 =
years,
even with foot dragging. I'm expecting us to start seeing IPv4 actually =
deprecated
as in some providers won't route it any more (or if they do, they'll =
charge a lot
to do so) in 6-11 years. That's what I mean when I say I'd like to see =
IPv4
go away in that time frame.
Owen
