Establishment of Optimal Disjoint Paths in MPLS Networks

MPLS is an IETF-Specified framework providing high reliability of routing, switching & forwarding of traffic flows through the network. Recent augmentation in the internet traffic has made QoS a necessity for large-scale networks. MPLS is currently gaining high values in corporate sector to carry some high value traffic components, such as telephony over IP (ToIP) or VPN’s and for such a service, availability is a critical QoS dimension that needs to be protected from network failures. In order to preserve other QoS requirements, the paths must meet certain constraints (e.g., bandwidth availability & low load) and/or minimize some metric (e.g., minimum hop counts or hop counts with minimum delay). Among the problems that remain unsolved is how to efficiently find & establish optimal primary and backup LSP’s for mission critical services subjecting to QoS constraints. So, in regards to this context we will study three alternative schemes recently proposed [1] for diverse path computation & assess their performance in terms of some QoS metrics as mentioned above, describing the critical problems faced in the research process & present our vision on how to rationally overcome some of the problems exposed