<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=utf-8"><meta name=Generator content="Microsoft Word 12 (filtered medium)"><style><!--
/* Font Definitions */
@font-face
{font-family:宋体;
panose-1:2 1 6 0 3 1 1 1 1 1;}
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:"\@宋体";
panose-1:2 1 6 0 3 1 1 1 1 1;}
@font-face
{font-family:Verdana;
panose-1:2 11 6 4 3 5 4 4 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:宋体;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-reply;
font-family:"Calibri","sans-serif";
color:#1F497D;}
.MsoChpDefault
{mso-style-type:export-only;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 90.0pt 72.0pt 90.0pt;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><body lang=ZH-CN link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:10.5pt;font-family:"Calibri","sans-serif";color:#1F497D'>In the measurement of ATR, APNIC’s experiment eliminated the possible sampling bias by counting users (20.8% failure rate) other than counting resolvers (50% failure rate)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.5pt;font-family:"Calibri","sans-serif";color:#1F497D'><a href="http://www.potaroo.net/presentations/2018-05-16-atr.pdf">http://www.potaroo.net/presentations/2018-05-16-atr.pdf</a><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.5pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.5pt;font-family:"Calibri","sans-serif";color:#1F497D'>There are possible ways to hide IPv6 large response issue from end users: 1) re-query to different NS server (still around 80% chance);2) Finally fallback to TCP after failed re-queries; 3) IPv4 DNS …. <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.5pt;font-family:"Calibri","sans-serif";color:#1F497D'> DNS is suffered and become a little slow ,but not broken. <o:p></o:p></span></p><p class=MsoNormal><a name="_MailEndCompose"><span lang=EN-US style='font-size:10.5pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></a></p><p class=MsoNormal><span lang=EN-US style='font-size:10.5pt;font-family:"Calibri","sans-serif";color:#1F497D'>Davey<o:p></o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0cm 0cm 0cm 4.0pt'><div><div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><p class=MsoNormal><span lang=EN-US><br>The resolvers that are doing DNSSEC validation and thus request the<br>DNSKEY RRset, are likely predominantly not behind broken home CPE<br>routers and the like, and/or fail over to IPv4. So the actual<br>impact may be low.<o:p></o:p></span></p></blockquote><div><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div><div><div><p class=MsoNormal><span lang=EN-US style='font-family:"Verdana","sans-serif"'>Yeah, that is what I was trying to say with sampling bias -- the people who run validating recursives may be "more able" than those who don't to get the packets?<o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-family:"Verdana","sans-serif"'><o:p> </o:p></span></p></div></div></div><div><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></div></div></div></body></html>