Multi-constraint-pruning: an algorithm for finding K shortest paths subject to multiple constraints

The main task of network resilience research is: when network is failure how to find a replacement path for the affected business as soon as possible, and also guarantee the quality of service (QoS). Different businesses have different QoS needs, in order to find a best resilience routing for different business, we need to take into account a variety of constraints, it has also increased the routing complexity. In this paper, a new algorithm to calculate the first K multiple-constrained-shortest-paths (KMCSP) in a given constraints network has been presented. We call it multi-constraint-pruning algorithm. The algorithm is able to calculate the k shortest paths based on the required constraints weights. In different QoS, the weight of different priority for each constraint would be considered in the algorithm. The program we wrote for multiple-pruning algorithm is able to list the KMCSP for different QoS, and draw a graphic represent the KMCSP. After extensive experiments in Matlab environment, the feasibility and speed improvement of algorithm has been proved in this paper.