Hey, > Well, now there is no IPv4. But BGP, OSPFv3, and other routing protocols > still use 32-bit router IDs for IPv6. On the one hand, there are plenty of > 32-bit numbers to use. Generally speaking, router IDs just need to be unique > inside of an AS to do their job, but (a) for humans or automation to generate > them and (b) to easily recognize them, it's convenient to have some algorithm > or methodology for assigning them.
2nd hand knowledge, but when this was discussed early on in standardization, someone argued against 128b ID, because it would require too much bandwidth in their OSPF network. Joys of everyone plays standardisation. > Has anyone thought about this or have a good way to do it? We had ideas like > use bits 32-63 from an interface. Seems like it could work, but also could > totally break down if we're using >64-bit prefixes for things like > router-to-router links or pulling router loopbacks out of a common /64. If your data is in a database I think the best bet is to algorithmically generate multiple forms of IDs in your device and interface rows, to satisfy various restrictions on what forms of IDs are accepted. And then use these IDs. If your data is in configs, you don't have really good solutions, but you could choose 32b from your IPv6 loopback right side :/. -- ++ytti
