Google and IPv6

[Larry J. Blunk]

Kevin Day wrote:
>
> On Mar 16, 2008, at 9:34 PM, Erik Kline wrote:
>> Speaking personally, I have seen analysis of neither client behaviour
>> nor connectivity in the IPv6 Internet today.  Are things really as bad
>> as folks say or is it partly a kind of "urban legend of horribleness"
>> that persists from earlier tests with less-mature operating systems
>> and less reliable connectivity?  I  just have 6to4 at home and my Mac,
>> Linux, and XP boxes all seem to work just fine.
>
> Every few months I've performed this test on a rather high traffic 
> (but probably tiny compared to what you're used to) website that's 
> comprised mostly of completely non-technically savvy users. The reason 
> I feel the "non-technical users" part is important is because if one 
> of us realizes that we can't reach www.ripe.net, we go fix it - most 
> users think "oh, the internet is broken" and move on to something 
> else. This results in problems going unresolved. :)
>
> On one page of this site, we put two 1x1.gif images.
>
> ipv4.gif is on a hostname that has only a v4 A record. This gets a 
> baseline of how many people loaded the images on the site at all.
> 4or6.gif is on a hostname that has both AAAA and A records.
>
> The order the two images appeared on the page was randomized on every 
> page load to try to reduce any bias there. I measured how many times 
> each image was loaded after a few hours. Results from the last time I 
> attempted this, after removing duplicate IPs:
>
> ipv4.gif was loaded 278821 times.
> 4or6.gif was loaded 278704 times. (191 hits were on the v6 IP, 278513 
> on the v4 IP)
>
> The good news is that 0.069% of our viewership was able to load an 
> image on the v6 IP of an AAAA record. Nearly all of these were 6to4 
> addresses, with a few Teredo. I only saw 2 IPs that looked like native 
> v6.
>
> The bad news is that the image on the AAAA record was loaded 0.042% 
> less than the one on the A record. This meant that by publishing an 
> AAAA record, your site would appear broken to almost as many users as 
> would benefit from having the v6 connectivity.
>
> I did some troubleshooting with as many users as I could that were 
> willing to look at why they weren't able to access the host on the 
> AAAA record, but didn't get very far with most of them before they 
> lost interest with troubleshooting. In most cases it seemed like users 
> had ended up with v6 activated/configured when they had no v6 
> connectivity. None of the problems appeared to be broken v6 
> connectivity exclusive to our site - if the user couldn't reach our 
> site on an AAAA record, they couldn't reach any AAAA hostnames.
>
> -- Kevin


  I had problems getting to ARIN's IPv6 website for a number
of months due to a tunnel and path MTU issues.   The TCP
session would get established, but then it would hang because
the subsequent larger packets could not get through.   A 1x1.gif
image would probably make it through fine, so I would suggest
testing with something > 1500 bytes.

 -Larry Blunk
   Merit