Evaluation of reliability for a cloud computing system through multiple minimal paths subject to maintenance budget

摘要

The cloud computing system (CCS) is structured by powerful servers that afford to compute a large amount of data for the remote clients. To keep a good quality of service, the maintenance action should be taken when the CCS falls to a specific state such that it cannot afford enough capacity to satisfy demand d. In order to reduce the transmission time that data travels from the cloud to the client, several disjoint minimal paths are utilized to send data simultaneously. Given the maintenance budget B and within time T, we evaluate the probability that d units of data can be sent from the cloud to the client, where such probability is named system reliability. To evaluate 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 system reliability can be computed in terms of such vectors by applying the recursive sum of disjoint products algorithm.