Reliability and criticality analysis of communication networks by stochastic computation

Reliability is an important feature in the design and maintenance of a large-scale network. In this article, the reliability of information transmission between a transmitter and a receiver (i.e., a two-terminal network) is considered as a generalized connectivity framework of terminal nodes. As network complexity increases, existing approaches to reliability analysis are encountering significant challenges. In this article, stochastic computational models are presented to efficiently analyze the reliability and criticality of a two-terminal network. Non-Bernoulli sequences with fixed numbers of 1s and 0s are utilized to encode the signal probabilities, and improve computational efficiency and accuracy. Both unidirectional and bidirectional links are considered for the probabilistic information transition process by imperfect links. Imperfect nodes are also modeled by the stochastic model of an imperfect unidirectional link. Non-exponential failure distributions and correlated signals in a two-terminal network are readily handled by the stochastic approach. The reliability of a system with external deterministic failures on a link is compared to that of the system prior to the occurrence of the failures. The difference in reliability is referred to as the criticality of the link. An analysis is pursued for the critical links based on the value of criticality. The proposed approach can be used to analyze and improve network reliability when utilizing limited redundancy for protecting the links.