Cooperative security in distributed networks

We consider a distributed network in which faulty nodes can pose serious threats as they can subvert the correct operation of basic functionalities, such as, routing or data aggregation. As a setoff to such nodes, we suggest that trust management between nodes is an essential part of a distributed system. In particular, benign nodes shall communicate with trusted nodes only and misbehaving nodes must be rapidly removed from the system.This paper formalizes the concept and properties of cooperative security – a protocol which allows implementing trust management by means of two voting procedures. During the first voting – admission procedure – each node gains trust by distributing revocation information to its neighbors. These neighbors form the node’s trusted entourage. If the node cooperates and discloses enough information, it is admitted and can communicate with the rest of the network; otherwise it is rejected. If the admitted node tries to endanger the network the second revocation voting procedure takes place. In this case, if the node’s entourage agrees upon act of misbehavior they revoke the node network-wide using previously disclosed revocation information.