Towards Modelling Information Security with Key-Challenge Petri Nets

Our global information society is based on distributed wide-area networks. Network security consists of the provisions made in an underlying computer network infrastructure, policies adopted by the network administrator to protect the network-accessible resources from unauthorized access, as well as continuous monitoring and measurement of the network security's effectiveness. In this paper, we describe the use of Petri nets in modelling network security. We propose a new hierarchical method for modelling network attacks and evaluating effectiveness of the corresponding defences. Our model is called Key-Challenge Petri Net (KCPN).