On Tue, 20 Apr 2004, Crist Clark wrote:
But it has limited effectiveness for multi-hop sessions. There is the appeal of a solution that does not depend of the physical layout of the BGP peers.
Does MD5 open the door to cpu DOS attacks on routers though? Eg can someone craft a DOS attack to take out the CPU on a router by forcing it to MD5 authenticate torrents of junk packets, using less bandwidth than it would take to DOS the links themselves? As has been pointed out, blind attacker needs to guess the source port as well, which would seem to multiply the search space blind attackers need to hit (the tcpsecure paper states as much - "assuming the attacker can accurately guess both ports") Are such attacks still practical in that light? -Dan