Iljitsch van Beijnum writes:
Well, if they had problems like this in the past, then I wouldn't trust them to get it right. Which means that it's probably a good idea if EVERYONE starts filtering what they allow in their tables from PCCW. Obviously that makes it very hard for PCCW to start announcing new prefixes, but I can't muster up much sympathy for that.
So basically, rather than generate routing registry filters for the entire world, generate routing registry filters for known careless ASes. This number should be small enough that this is somewhat doable. [...]
Maybe, but how much would that help? So you suggest that we only need to filter against AS7007, AS9121, and AS17557. Personally, those are among the ones I least worry about - maybe I'm naive, but I'd hope they or their upstreams have learned their lessons. The problem is that nobody knows which of the other 25000+ ASes will be the next AS7007. So I guess we have to modify your suggestion somewhat and, in addition to filtering the "known-careless" also filter the "unknown-maybe-careful" class. Oops, that leaves only the "known-careful" class, which includes... my own AS, and then whom? -- Simon.