> From: Ole Troan <otroan@xxxxxxxxxxxxx> >> IPv6 Neighbour Discovery is just the thing. I gather it's turned >> off on 6to4 links > IPv6 Neighbour Discovery requires a multicast capable link and > support for link-local addresses. Well, RFC-4861 does say: Unless specified otherwise ... this document applies to all link types. ... it is possible that on some link types (e.g., Non-Broadcast Multi-Access (NBMA) links), alternative protocols or mechanisms to implement those services will be specified ... services described in this document that are not directly dependent on multicast, such as Redirects, Next-hop determination, Neighbor Unreachability Detection, etc., are expected to be provided as specified in this document. 6to4 (especially anycast 6to4) should/would be considered an NBMA link, and the spec does say (for such links): Redirect, Neighbor Unreachability Detection and next-hop determination should be implemented as described in this document. So I don't see that it's wildly inappropriate. > NUD could be made to work, but I don't think NUD is any better than > any other connectivity test. e.g. a "BFD echo" style one as I only suggested doing reachability detection by turning on ND as an simple, easy way to do it - one would avoid having to write a bunch of code (which one would have to, in order to use, say, an ICMPv6 ping based mechaniam). But this isn't the right place for a detailed discussion - which is probably OBE anyway - so I will leave it there. Noel _______________________________________________ Ietf mailing list Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf