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<p class="MsoNormal"><span style="font-size:11.0pt;color:black">Hello,</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black"> </span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">As we are trying to tighten the security for IPv6 traffic in our network, I was looking for a reference IPv6 ingress filter.</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">I came up with Job Snijders suggestion (thank you Job) that can be conveniently found at whois -h whois.ripe.net fltr-martian-v6</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black"> </span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">After applying the filter I noticed some traffic from 6to4 addresses (2002::/16) to our native IPv6 prefixes (residential users in this case).</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">The traffic is a mix of both UDP and TCP but all on high port numbers on both destination and source.</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">It seems to me like some P2P traffic, but I really can’t tell.</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black"> </span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">This got me thinking, why should we filter these addresses at all ?</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">I know 6to4 is mostly dead, but is it inherently bad ?</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black"> </span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">And if so, why is the prefix (2002::/16) still being routed ?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">I would love to hear some thoughts on this, and understand if others are actually filtering this at both data plane and control plane.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black"> </span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">Thanks,</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black"> </span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">Amos Rosenboim</span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;color:black">-- </span><span style="color:black"><o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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