[Background] Security risk assessment methods in industry mostly use a tabular notation to represent the assessment results whilst academic works advocate graphical methods. Experiments with MSc students showed that the tabular notation is better than an iconic graphical notation for the...

Modern access control models, developed for protecting data from accesses across the Internet, require to verify the identity of users in order to make sure that users have the required permissions for accessing the data. User's identity consists of data, referred to as identity attributes, that...

Trust negotiation is a promising approach for establishing trust in open systems, in which sensitive interactions may often occur between entities with no prior knowledge of each other. Although, to date several trust negotiation systems have been proposed, none of them fully address the problem...

Blockchains and Byzantine Fault Tolerance form the basis of decentralized currencies and ledgers such as Bitcoin, Ripple, ZeroCash, and Ethereum. A large slate of literature has focused on the currency aspects (e.g. anonymity, independence from central banks, etc.). We argue that, as-far-as...

This study addresses various issues in the study of interdependent cyber security, and sheds light on the economic and policy implications of increasing security interdependence. We investigate the impact of a policy arrangement affecting security interdependence on agents' regulated and...

Determining the transition matrix of a discrete Markov process from sequential forecasts of smoothed density functions is an important element of many problems in decision theory and economics. Recent theoretical results have demonstrated that the Perron-Frobenius eigenfunction of a Markov risk...