Probabilistic Protection for Both Computing and Transmission Capacities of Virtual Networks Under Multiple Facility Node Failures

This paper proposes a backup computing and transmission capacity allocation model for virtual networks that minimizes the required backup computing capacity under multiple facility node failures. The proposed model adopts the probabilistic protection, where the probability that the protection fails due to insufficient capacity is restricted not to be greater than a given survivability parameter, by using robust optimization. The conventional model allocates the backup computing capacity by considering the probabilistic protection but allocates the transmission capacity for all backup paths dedicatedly. The proposed model allocates the backup transmission capacity only for the failure patterns that are considered under the probabilistic protection guarantee; the probabilistic protection is considered for both computing and transmission capacity allocation. Reducing the required backup transmission capacity can also reduce the required backup computing capacity, since more feasible solutions for backup computing capacity allocation can exist. We introduce a heuristic algorithm to solve the backup computing and transmission capacity allocation problem. Numerical results show that the proposed model reduces the required backup transmission capacity and enhances the feasibility of allocating virtual networks compared with the conventional model. We also observe that reducing the required backup transmission capacity can lead to reducing the required backup computing capacity.