Optimal LSP selection method in MPLS networks

Multi-protocol label switching (MPLS) had been deployed by many data networking service providers because of its undeniable potential in terms of virtual private network (VPN) management, traffic engineering, etc. In MPLS networks, IP packets are transmitted along a Label Switched Path (LSP) established between edge nodes. To improve the efficiency of resource use in MPLS networks, it is essential to utilize the LSPs efficiently. This paper proposes an optimal LSP selection method in MPLS networks, on the assumption that both the upward and downward LSPs are established as a pair (both-way operation) and multiple LSP pairs are established between the same pair of edge nodes. It is supposed that the optimal LSP pair is selected from among multiple LSP pairs for each service request and both upward and downward bandwidths are allocated simultaneously in the selected LSP pair. It is demonstrated by simulation evaluations that the proposal method could reduce the total amount of the bandwidth required by up to 15% compared with the conventional selection method.