Other-Sean writes: | Other than making it difficult for people to figure out WHOIS using that | ASN, "yanking" an ASN's registration has little practical effect. You | can use an un-allocated ASN almost as easily as using an un-allocated | address block. Well, the hidden point here was that the registries act on behalf of the communities of ISPs who form the registries' paying customer base / membership, and there is no particular reason why they could not alert their membership to "evil doers". What is done with such an alert is of course up to each individual member/network, however I imagine several of them would set up filtering, perhaps including the ones closest to the source of the "evil doing". Obvious candidates for reportable behaviour include the use of unregistered prefixes and ASNs. In the past in the odd case where an addressing registrar asked for assistance in dealing with such a thing she or he had discovered, I was happy to provide it. Sean.