Reliability evaluation of a computer network in cloud computing environment subject to maintenance budget

This paper measures the performance of a computer network in the cloud computing environment. To retain a good quality of service (QOS), the computer network is required to preserve a sufficient capacity level so that it can send d units of data from the source (a cloud computing center) to the sink (a set of clients) through multiple paths within time T. Thus, the maintenance action should be taken when the computer network falls to a specific state so that it cannot provide sufficient capacity to satisfy demand d. Given the maintenance budget B and time constraint T, we evaluate the probability that d units of data can be sent from the source to the sink, where the probability is referred to as the system reliability. A branch-and-bound approach including an adjusting procedure is proposed to obtain all minimal capacity vectors satisfying d, B, and T. Subsequently, the corresponding system reliability can be derived in terms of such vectors by applying the recursive sum of disjoint products algorithm.