Cost minimization for deadline-constrained bag-of-tasks applications in federated hybrid clouds

A mathematical programming model is proposed for a resource allocation problem in federated clouds, where bag-of-tasks (BoT) applications are assigned to instance types with different costs and performance levels. The proposed model is a binary linear programming problem containing deadline and resource constraints in the cloud federations and by the objective of minimizing the total cost of applications. These constraints and objective are explicitly expressed using mathematical functions, and the model is solved with the CPLEX solver. This paper also discusses a post-optimality analysis that deals with stability in assignment problems. Numerical results show that the optimal cost and optimal solutions in the cloud federations are lower and more stable, respectively, than those presented by single-provider clouds. In contrast to optimality in single-provider clouds, that in the cloud federations is less sensitive to input data.