An efficient and scalable resource monitoring approach for MPLS-enabled IP networks

Abstract

This paper studies the network resource monitoring issues in MPLS enabled IP networks. First it analyzes the MPLS use cases, relevant standards and various MPLS management proposals. Some basic concepts relevant to MPLS network resource management are clarified such as 1) Label Switched Path (LSP) route selection method, 2) LSP setup method, 3) LSP computation method and 4) LSP deployment mode. It is shown that, among all the technical method alternatives, the combination of the explicit routed and control plane signaled LSP makes the resource management task more complicated and challenging. Then, the network topology discovery functionality is found to be different in MPLS networks than in the conventional IP networks. The existing IP topology discovery method can’t provide an accurate and up-to-date topology database, which is critical for the dynamic resource management. A new method named LSP feedback, which piggybacks the MPLS topology information on the reverse messaging of the label distribution protocol, is introduced. The LSP feedback method has advantages in its high accuracy, more up-to-date and low overhead. But it still has some drawback such as lack of global topology information on the routing domain. This document proposes two approaches to enhance the LSP feedback method. Finally, a bandwidth limit calculation algorithm is described in details.