LSP restoration in MPLS network using case-based reasoning approach

Today the Internet has serious problems of an explosive increase of traffic caused by increased numbers of users. These problems degrade prominently the quality of service (QoS), and make it difficult to provide multimedia and real time services. Various technologies are proposed to solve these problems. Especially, MPLS (multiprotocol label switching) was developed for the Internet backbone network. The faults occurring in high-speed networks such as MPLS may cause massive data loss and degrade QoS. To deliver a reliable service, however, MPLS requires a set of procedures to provide a suitable protection for the traffic carried on the label switched paths (LSPs). This paper proposes an enhanced scheme for fast rerouting to preassigned LSPs in case of LSP or link failures. In order to minimize back-up resources, it allows possibility of splitting traffic of faulty LSP onto available alternative LSPs for fault recovery. We use preassigned LSPs for restoration when fault occurs. Total traffic throughput and resource utilization can be maximized if the traffic of faulty LSP is split over multiple pre-assigned LSPs. In this paper a new approach to providing fault tolerance in MPLS networks using case-based reasoning as a method to find out the amount of traffic forwarded on each pre-assigned LSP based on past experiences if loading process is presented. The pre-assigned LSPs and the percentage of traffic splitting are calculated off-line based on desired QoS and capacity constraints.