Fault-tolerant system design on cloud logistics by greener standbys deployment with Petri net model

The cost-aware exploration on enhancing fault-tolerant becomes an important issue of service quality from cloud platform. To approach this goal with greener design, a novel server backup strategy is adopted with two types of standby server with warm standby and cold standby configurations. On such two-level standby scheme, cost elaboration has been explored in terms of deployment ratio between warm standbys and cold standbys. The cold standbys provide a greener power solution than those of conventional warm standbys. The optimal cost policy has been proposed to maintain regulated quality of service for the cloud customers. On qualitative study, a Petri net is developed and designed to visualize the whole system operational flow. On quantitative research for decision support, the theory of finite source queue is elaborated and relevant comprehensive mathematical analysis on cost pattern has been made in detail. Relevant simulations have been conducted to validate the proposed cost optimization model as well. On green contribution, the saving of power consumption has been estimated on the basis of switching warm standbys into cold standbys, which amounts for the reduction of CO2 emission. Hence the proposed approach indeed provides a feasibly standby architecture to meet cloud logistic economy with greener deployment.