Approximate and accurate maintenance reliabilities of a cloud computing network with nodes failure subject to budget

In a practical cloud computing network (CCN), edges and nodes perform various capacities or states due to failure, partial failure, or maintenance. Thus, the CCN is a typical stochastic-flow network. To guarantee a good quality of service (QoS), the CCN should be maintained, so as not fall into a failed state whereby it cannot provide sufficient capacity to satisfy demand. Therefore, maintenance reliability is developed to evaluate the capability of the CCN to send d units of data from the cloud to the client through two paths under both the maintenance budget and time constraints. We integrate two procedures in the proposed algorithm-an approximation procedure for approximate maintenance reliability and an adjusting procedure utilizing the branch-and-bound approach for accurate maintenance reliability. Subsequently, the approximate maintenance reliability with lower and upper bounds, and the accurate maintenance reliability are computed by applying the recursive sum of disjoint products (RSDP) algorithm.