Design and implementation of a scalable constraint-based routing module for QoS path computation

Quality of Service in computer networks depends on several variables like bandwidth, delay, jitter, cost, and packet loss which affect the overall user experience. In Multiprotocol Label Switching Networks, paths can be established end-to-end and resources can be guaranteed on each hop. However, due to several reasons, among them the computational cost involved, these paths are normally computed with constraints for only one variable. In this paper we propose a design and implementation of a scalable module for multi-constraint path computation in the context of the Path Computation Element architecture. We present all the design issues involved in an integral solution that accounts for all problems involved, some examples of the problem, and a scalable architecture to solve it. Finally, we present our performance results on simulated scenarios and real world networks.