[137915] in North American Network Operators' Group
Re: [arin-ppml] NAT444 rumors (was Re: Looking for an IPv6
daemon@ATHENA.MIT.EDU (Benson Schliesser)
Tue Feb 22 17:16:28 2011
From: Benson Schliesser <bensons@queuefull.net>
In-Reply-To: <7277A6F9-C21C-4EF0-8220-A3F3A707A836@delong.com>
Date: Tue, 22 Feb 2011 16:16:11 -0600
To: Owen DeLong <owen@delong.com>
Cc: NANOG list <nanog@nanog.org>, ARIN-PPML List <arin-ppml@arin.net>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Feb 22, 2011, at 3:40 AM, Owen DeLong wrote:
>> There seems to be a position, taken by others on these lists, that =
IPv6 is the only address family that matters. Interestingly, this =
position seems to be most pronounced from people not involved in =
operating production networks. But, regardless, if I were to accept =
this position then I might also agree that it doesn't matter whether or =
not draft-donley-nat444-impacts is misleading.
>>=20
> I don't think anyone has said that IPv6 is the only address family
> that matters. What I think people, myself included, have been saying
> is that IPv6 is the only way forward that does not involve many of =
these
> problems. (See my earlier Titanic post).
I agree completely: IPv6 is the only way forward that avoids these =
problems. In fact, an understanding of CGN impacts should be enough =
motivation for operators and users to start deploying IPv6 immediately.
> As to whether or not it matters that people misinterpred =
draft-donly...,
> I'm not sure whether it actually does or not. There is no flavor of =
NAT
> that is particularly desirable. It's a matter of choosing the one that =
is
> least damaging to your environment where least damage may
> boil down to a choice between 5% and 3% remaining functionality.
I agree with your sentiment, that we should choose the least damaging =
solutions. Call it the "lesser evil" if you'd like.
However, I think your estimates (5% vs 3%) are backwards. CGN-based =
solutions work for the vast majority of network traffic today - it's the =
stuff in the margin that breaks, according to all test reports I've =
seen.
> I don't think anyone is saying IPv4 no longer matters. I think we are
> saying that effort spent attempting to make the deteriorating IPv4
> situation deteriorate less is both futile and better spent on making
> the IPv6 deployment situation better.
It's not an exclusive situation - we can roll out IPv6 while continuing =
to maintain our existing IPv4 connectivity, support new customers with =
IPv4 needs, etc. As I mentioned before, we have to support the bridge =
we're crossing (crumbling IPv4 infrastructure) until we're on the other =
side (fertile IPv6 farmland).
>> Of course, we can also rely on an IPv4 address market to avoid NAT in =
the more sensitive situations (i.e. situations with more sensitive =
users). But that's a different conversation.
>>=20
> Only if you expect that you can rely on a supply side in such a =
market.
> I am unconvinced that such will be reliable, especially after about 6
> months of trading. This also presumes that more sensitive users can
> be defined in terms of what those users are willing (or able) to pay.
This is an interesting discussion, because the timeframe is central to =
everything I've commented above.
Considering RIR exhaustion (4-12 months) plus ISP exhaustion (TBD, but =
let's say anywhere from 1 month to 5+ years after RIR exhaustion), I =
expect some network providers to struggle with IPv4 address exhaustion =
before the 3rd quarter of 2011. On the other hand, other network =
providers will have enough resources to last for years - let's call that =
"excess supply".
By all realistic estimates, any network provider that hasn't deployed =
IPv6 support into their infrastructure will need anywhere from 3 months =
to 3 years or more - let's generously say around 18 months to the point =
where 60% - 80% of hosts have reached IPv6 connectivity. Just =
considering these facts, I think we can see why some ISPs might be =
interested in acquiring more addresses through 2012. And those with =
excess supply might be motivated (financially) by a marketplace to share =
their resources, to meet this need.
Further, let's consider that some network services (such as content / =
hosting) will need IPv4 connectivity longer than others, in order to =
reach the long-tail. For this category, I can see why some networks =
might be interested in acquiring more addresses through 2013 - 2016. =
Fortunately, on the other side of 2012 prices should decrease because =
supply goes up (as some people give up IPv4). Thus the market value of =
an address probably can be represented by a curve peaking in a couple =
years and then declining to zero a few years after that.
Feedback on this would be appreciated - but my current belief is that =
it's realistic to plan for a couple years of trading rather than "about =
6 months".
(Side note: If we really wanted people to move to IPv6 before now, we =
should have instituted increasing prices for RIR-provided addresses. I =
posit that we just didn't have the collective balls to do this.)
Cheers,
-Benson
