On 17-May-19 06:34, David Farmer wrote: > > > On Thu, May 16, 2019 at 1:20 PM Sander Steffann <[email protected] > <mailto:[email protected]>> wrote: > > Hi David, > > > While I happen to agree with you 2002::/16 SHOULD NOT be filtered, and > RFC 7526 is quite clear that 2002::/16 is still valid. However, it is > perfectly permissible to filter it, if that is the policy a network operator > wishes to enforce. > > With the 6to4 anycast relays deprecated the only 6to4 traffic should be > src 2002::/16 and dst 2002::/16. Sites that are not using 6to4 themselves can > filter 2002::/16. Everybody else will only see IPv4+proto41 traffic, which is > not impacted by that filter. > > > NO! RFC3056 Includes a gateway functionality it is just not Anycast.
Indeed. The Anycast hack was invented some time after 6to4 was standardised, and for a completely different purpose. Filtering the 6to4 IPv4 anycast address is a sensible thing to do for an IPv6-supporting ISP. Filtering 2002::/16 is unnecessary and breaks harmless traffic. (And there is so little such traffic that it is truly harmless.) Brian > It is possible to locally gateway traffic to native IPv6 and then you would > get traffic sourced from 2002::/16 and then you need to send traffic to a > return gateway. Now, most traffic you are seeing is probably coming from the > public anycast gateways that are still running, but it doesn't have to be. As > I said elsewhere in the thread, it complicated and filtering is easy. Read > RFC7526 very carefully, if you care, if you don't just filter it. > > Thanks > -- > =============================================== > David Farmer Email:[email protected] > <mailto:email%[email protected]> > Networking & Telecommunication Services > Office of Information Technology > University of Minnesota > 2218 University Ave SE Phone: 612-626-0815 > Minneapolis, MN 55414-3029 Cell: 612-812-9952 > ===============================================
