Distributed Bayesian Network Trust Model in Virtual Network

Network virtualization is a promising concept to diversify the Future Internet architecture into separate Virtual Networks (VN) that can co-exist over a shared substrate network. To take full advantage of this paradigm this paper proposed a distributed trust model of VNs or services provided by VNs based on the Bayesian Network. The trust model is carried out by the trust model engine (TME) which develops a naïve Bayesian Network for each VN and collects the evaluation information submitted by the users after interactions with VNs to maintain a responding conditional probability table (CPT) for the trust valuation. Due to the large number of VNs or services, TMEs should be deployed in different domains to reduce the complexity of computation. In addition, the old trust value should be taken into account when updating the new trust value. This can be achieved by introducing a longevity factor which controls the rate at which old evaluations are aged and discounted as a function of time. The experimental results of the model show that the model with longevity factor is more desirable.