PAID: A Probabilistic Agent-Based Intrusion Detection system

In this paper we describe architecture and implementation of a Probabilistic Agent-Based Intrusion Detection (PAID) system. The PAID system has a cooperative agent architecture. Autonomous agents can perform specific intrusion detection tasks (e.g., identify IP-spoofing attacks) and also collaborate with other agents. The main contributions of our work are the following: our model allows agents to share their beliefs, i.e., the probability distribution of an event occurrence. Agents are capable to perform soft-evidential update, thus providing a continuous scale for intrusion detection. We propose methods for modelling errors and resolving conflicts among beliefs. Finally, we have implemented a proof-of-concept prototype of PAID.