Detecting DoS attacks in mobile agent systems and using trust policies for their prevention
In the world of mobile agents, security aspects are extensively being discussed. Denial of service (DoS) attacks are of considerable interest, i.e., when malicious hosts either delete received agents or prevent them from continuing their route. We present a method for a posteriori identification of such malicious hosts in order to enable the agent's owner to build a trust policy. Depending on how much the agent owner trusts the hosts, he can either define an appropriate order in which selected hosts should be visited, or he can decide which hosts he does not want to contact again. The proposed protocol takes into account the visiting order constraints of the hosts which arise due to the dependencies of the computation results on an agent's journey. We also show how the sequence of hosts should be determined in order to minimize some costs.