Hi, During the OSPF meeting (taking place now), Abhay recently asked why IPv6 link-local addressing is not a sufficient solution for OSPFv3 deployments (with AF extension) in IPv4-only networks.
As we discussed during the meeting, there are some deployed link types that do not yet support IPv6 packets *at all*. However, one imagines that over time, such links will have equipment upgrades to have full dual-stack (IPv4 + IPv6) support. Using OSPFv3/IPv4 now with the AF extension -- and later migrating to OSPFv3 -- can reduce operations costs significantly in at least some deployments that I'm familiar with. For example, some deployed IP/VSAT terminals either (A) have Ethernet interfaces that only support ARP and IPv4 [e.g., using EtherType to filter in hardware] OR (B) have serial interfaces that again only support IPv4/PPP packets. ASIDE with more context: For those who don't use SATCOM much, The term VSAT is precisely defined as "Very Small Aperture Terminal". "Very Small Aperture" typically means that the SATCOM dish on the ground is roughly 1m in diameter, rather than the rather larger SATCOM dishes used in some other deployments. VSATs are quite commonly used around the whole globe, in both developed and less developed regions. Within North America they commonly are used to connect retail sites (e.g. banks, petrol stations, consumer electronics stores) back to the central site for that business. Separately, it would not be odd for a VSAT deployment to have an uplink speed that is ~10% of the downlink speed. Yours, Ran Atkinson _______________________________________________ OSPF mailing list [email protected] https://www.ietf.org/mailman/listinfo/ospf
