<div style="font-family:arial,helvetica,sans-serif;font-size:10pt">On Wed, Nov 21, 2012 at 11:10 AM, Doug Barton <span dir="ltr"><<a href="mailto:dougb@dougbarton.us" target="_blank">dougb@dougbarton.us</a>></span> wrote:<br>
<div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="im">... and with this perspective I sympathize, but I think the reality is that we are going to have wacky IPv6 connectivity problems well into the next decade, during the long ramp-up of knowledge and experience on both sides of the network.</div>
</blockquote><div><br></div><div>Our numbers disagree. For users of MSIE on Windows Vista/7 (i.e., a combination with no happy eyeballs at all), aggregate reliability to Google dual-stack sites is over 99.95% of aggregate reliability to Google IPv4-only sites. If you exclude Japan, which has its own special issues, and another handful of networks with chronic IPv6 problems that can be addressed using tactical fixes, that number goes even higher, coming pretty close to 99.99%. (Even though it's just started rolling out, the beneficial effect of the new Windows 7 on those numbers is substantial.)</div>
<div><br></div><div>I would argue that that kind of performance is acceptable for the vast majority of applications, especially given that random outages/failures are likely to lower IPv4-only reliability substantially below 99.95% anyway.</div>
<div><br></div><div>Yes, happy eyeballs can give you even more reliability, but it comes as a substantial cost in complexity, and given the reliability numbers we have today, it's not clear that it's worth it.</div>
<div><br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="im">We are also going to continue to see reluctance on both sides if the hosts/apps are not robust enough to handle said wacky networks without significant degradation to the user experience.</div>
</blockquote><div><br></div><div>The current level of IPv6 reliability has not stopped 5 of the top 10 global websites from deploying IPv6, nor has it stopped >60 major networks rolling out IPv6 to substantial percentages of their users (see the World IPv6 Launch measurements).</div>
<div><br></div><div>I would argue that as IPv6 growth continues, its importance will increase, and bugs will be fixed. And the best way to ensure bugs are fixed is to ensure someone notices - which is what Microsoft is doing.</div>
<div><br></div><div>Fear of IPv6 brokenness was a big reason for lack of IPv6 deployment for a few years, but I think we're past that now. The concerns are back to what they were before - no perceived business case, little demand from users, lack of support in equipment, and not a priority for the organization, and so on. And that is changing as IPv6 rolls out more widely and IPv4 address space comes under more and more pressure.</div>
<div><br></div><div>So I don't think we need to concentrate our efforts on this problem now, we just need to wait for operators to deploy it; the bugs will work themselves out. Of course it will take time, the Internet is a big network. But Google's public IPv6 numbers hit 1% this weekend, and growth was 2.94x year over year...</div>
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