Bo Hu

The Stable Paths Problem (SPP) is a widely adopted model for analyzing the convergence of Border Gateway Protocol (BGP). Solving SPP correctly is of great significance for determining BGP convergence. Existing studies have proposed some SPP solving algorithms that can only solve a part of SPP instances and have limited capabilities. To fill this gap, in this paper we transform SPP into Boolean Satisfiability Problem (SAT) and propose a new SPP solving algorithm called SPPsolver , which can support the solution of any SPP instance. We use Binary Decision Diagrams (BDD) to encode and calculate the SAT formula and apply two optimization methods to accelerate SPPsolver . We use real-world datasets to perform experiments and compare with state-of-the-art algorithms, the results demonstrate the superiority and efficiency of SPPsolver .

The current security risk assessment methods are of asset-center, which means that the security of assets, such as host, server and router, are assessed. Then the security risk of the whole network is aggregated. However, information is a kind of special asset that can flow across networks or systems, which is different from the general assets. Thus a kind of information-center risk assessment method is proposed. Firstly, the information spreading model is presented based on scale-free network in order to know how the sensitive information spreads. Then, based on the spreading threshold in the scale-free network, the information security risk is evaluated.