Hi Benedikt, > Hi Jim and list, > > first off, I've done some IPv6 multicast routing but I've never been > unlucky enough not to deal with it over IPv4. > > > 1) There is no MSDPv6 and probably never will be. Of course you > > have SSM and Embedded RP but that doesn’t cover all cases. For > > example – if you have a partnership with another organization and only > > want to share select multicast groups/sources then in IPv4 you use > > MSDP and MSDP filters. However, I don’t see how to do this with IPv6 > > multicast. > > Would it work if you used one of the available (unnamed) scopes for that > job? Agree on a scope that gets routed with your partner organization > and set up your border multicast routers accordingly.
Agreed - this is a viable approach. > > 2) Often I see different multicast domains with MSDP between them > > (including filters). Do organizations just do one huge PIMv6-Anycast > > domain and leave it at that? > > I'm not sure what you mean with "PIMv6-Anycast domain", but if I Basically something compliant with RFC 4610. With IPv4 I would use the approach described in RFC 3446. With IPv6 it seems like the replacement is "Anycast-RP using PIM" as described in 4610. My concern was using this approach for a large global backbone, but sounds like that's the only option. > understand your question correctly, then the answer is yes: One > (possibly anycasted) RP or set of RPs for all "multicast domains" (which > is a concept that doesn't really apply to IPv6) and matching scopes to So essentially I should stop thinking local "domains" and think globally for any IPv6 multicast deployment? > filter between the domains. (And yes, there may be constellations where > you actually run out of scopes...) > > If there is no direct connection between the domains, either use some > sort of VPN (which you'll likely have anyway) or possibly just a simple > GRE or configured 6in4 tunnel. Coming from an IPv4 Multicast background, I'm having a hard time accepting that my only Inter-domain RP option is embedded RP. I understand the issues with MSDP and why it wasn't extended to support IPv6. However, it still feels like there should be some kind of inter-domain RP communication/synchronization option. Perhaps I have not fully grokked IPv6 Multicast yet? Thanks, --Jim
