This isn't bad enough, not yet, for some kind of protocol that allows source quench / notify a remote ISP of a suspected infected host and suppress traffic from

This isn't bad enough, not yet, for some kind of protocol that allows source quench / notify a remote ISP of a suspected infected host and suppress traffic from said host. It would need to be out of band, and I suggest it use OpenPGP for signatures (chain of trust from IP allocating bodies), actually it would also need to query a database of allocated IP ranges.