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