Joe Abley writes:
http://www.ietf.org/internet-drafts/draft-turk-bgp-dos-04.txt
http://www1.ietf.org/mail-archive/working-groups/routing-discussion/current/msg00688.html
draft-marques-idr-flow-spec-00.txt seems to be sort-of a generalized
version of this (which doesn't necessarily mean that it's better).
--
Simon.