Transport Resource Manager for VPN routing in packet networks

Abstract

Traffic matrices play a crucial role in designing, dimensioning, and evolving communication networks. Recent measurement studies, however, found that there is generally a mismatch between traffic matrices and the actual network traffic. Since the link sizing and routing plans depend on the traffic matrix, this mismatch would result in inefficient use of the network resources. Traffic Engineering addresses this problem by utilizing alternate paths to distribute the traffic uniformly over the network. However, traffic engineering is applied at yearly or multi-year intervals, and may require re-routing of existing connections. In this paper, we introduce a route selection algorithm that operates during VPN set-up request arrivals to determine the best path for the incoming requests to achieve efficient use of the network resources. Our algorithm utilizes the concept of shadow prices and distributes the traffic uniformly across the network making better use of deployed network resources which in turn minimizes the network operator's overall infrastructure capital and operational expenses. The performance modeling results show that our solution outperforms shortest path and greedy routing algorithms. Furthermore, we show that an approximate lower bound, which may never be achieved by a feasible algorithm, is only 25% better in network cost compared to our solution.