IPv6 mistakes, was: Re: Looking for an IPv6 naysayer...

Owen DeLong owen at delong.com
Fri Feb 11 19:56:38 UTC 2011


On Feb 11, 2011, at 7:00 AM, Scott Helms wrote:

> 
>> I don't know about that.  Yes, v4 will be around for a long time but
>> considering the oligopolies we have in both eyeball and content
>> networks, ones a dozen or so very large networks switch, there is the
>> vast majority of Internet traffic right there.  It will be around for a
>> very long time handling a tiny bit of traffic.
>> 
> Agreed, V4 traffic levels are likely to drop and stay at low levels for decades.

I don't think it will be just a drop in traffic levels. I think that it will not be long
before the internet is an IPv6 ocean with islands of IPv4, much like it was
an ocean of IPv4 with islands of IPv6 years ago.

>> Facebook alone accounts for 25% of internet traffic in the US. Netflix
>> is estimated to be over 20% and YouTube at 10%.  So that's 55% of
>> Internet traffic right there.  At the other end of the transaction you
>> have AT&T with 15.7 million, Comcast at 15.9 million, Verizon at 9.2
>> million and Time Warner at 8.9 million (early 2010 numbers).  That's 50
>> million of the estimated 83 million US broadband subscribers.  So once
>> three content providers and four subscriber nets switch, that is over
>> 25% of US internet traffic on v6 (more than half the users and more than
>> half the content they look at).
> Comcast, nor the other large MSOs, are not as monolithic as they may appear from the outside.  In most cases the large MSOs are divided into regions that are more or less autonomous and that doesn't count the outlier properties that haven't been brought into the fold of the region they are in for various, usually cost related, reasons so don't expect a large block of any of those guys to suddenly be at 60% of their users can get IPv6 addresses.
> 
I think you'll be in for a surprise here.

> While Facebook working over IPv6 will be a big deal you won't get all of their traffic since a significant fraction of that traffic is from mobile devices which are going to take much longer than PCs to get to using IPv6 in large numbers.  Also, Netflix is even more problematic since the bulk of their traffic, and the fastest growing segment as well, is coming from Xboxes, Tivos, other gaming consoles, and  TVs with enough embedded brains to talk directly.  Those devices will also seriously lag behind PCs in IPv6 support.
> 
I think you'll be in for a surprise here, too. The 4G transition is already underway. For the vendors where 4G means LTE, IPv6 is the native protocol and IPv4 requires a certain amount of hackery to operate.

In the WiMax case (Gee, thanks, SPRINT), things are a bit murkier, but, I think you will see WiMax go IPv6 pretty quickly as well.

Yes, it will take a little longer to retire the 3G system(s) than many other parts of the internet, but, I think you will see most of it going away in the 5-7 year range.

>> I don't think the growth of v6 traffic is going to be gradual, I think
>> it will increase in steps.   You will wake up one morning to find your
>> v6 traffic doubled and some other morning it will double again.
> 
> They'll be jumps, but they will be fairly smallish jumps since both the content maker, the ISP, and the device consuming the content all have to be ready.  Since I don't imagine we will see any pure IPv6 deployments any time soon many/most of the IPv6 deploys will be dual stack and so we are still at the mercy of the AAAA record returning before the A record does.

You misunderstand how getaddrinfo() works under the hood. The code itself first does an AAAA lookup and then does an A lookup. DNS does not return both record sets at once. If there is an AAAA record, it will return first.

Some OS have modified things to resort the getaddrinfo() returns based on the perceived type of IPv6 and IPv4 connectivity available as an attempt to reduce certain forms of brokenness. However, even in those cases, you should get the AAAA first if you have real IPv6 connectivity.

Owen
> 





More information about the NANOG mailing list