A Novel Free-Roaming Mobile Agent Security Protocol against Colluded Truncation Attack by ACK

Protecting data of free-roaming mobile agents has drawn much attention in recent years. But no perfect solution has ever been proposed. Many of the solutions are vulnerable by colluded truncation attacks. In this study we analyze available methods, and design a novel protocol by cooperation between two kinds of agents -Task Agent and ACK Agent. Task Agent moves freely in the net to complete some task and returns to the user at last. Then, user creates ACK agent and it moves to the hosts who have been visited by Task Agent. ACK Agent is regarded as a response by the hosts and its itinerary is pre-defined. Any host who has been visited by Task Agent but not by ACK Agent can actively report to the user at proper time. This new protocol can detect colluded truncation attack, and locate the malicious hosts.