Daniel Roesen writes:
Well, it boils down that if you have enough customers, you seem to get away with about any antisocial behaviour on the net.
You don't need to have many customers, it's just more fun if you have a larger space that you can deaggregate. Since everybody stopped filtering you can deaggregate everything into /24s today and get away with it. So as soon as you have a /23 you can play. And there are just too many "valid reasons" to resist. Around here most ISPs, when they announce new customer routes, send mail to their peers saying "we will announce these prefixes under these paths, please update your filters". I often respond with a friendly note that we will filter this or that prefix because it's a more specific of a PA prefix (which we will actually do, although it doesn't matter that much since we always have a fallback). Sometimes I offer to put in a temporary (usually a year) filter exception so that they can renumber their new customer into aggregatable space. It doesn't help often, but sometimes it does. "Think globally, act locally." -- Simon.