A Sensitivity Analysis based Shortest Path Tree Restoration Approach for Link-State Routing Protocols

• Main Authors: Ching Jen, 曾敬任
• Other Authors: Huan Chen
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/35695642074428596799

碩士 === 國立中正大學 === 通訊工程研究所 === 97 === 　　IS-IS and OSPF are widely used intra-domain Link-State (LS) routing protocols. They are designed to enable all the routers in the routing domain to construct their routing tables consistently and efficiently. When the link state of the network changes, those LS routing protocols have to recompute new shortest path tree (SPT) for deriving new routing table. Unfortunately, it is unreasonable and inefficient to recompute entire SPT. Moreover, such recomputation will cause routing instability. In this paper, we proposed a novel SPT restoration scheme, called Sensitivity Analysis based Shortest Path Tree Restoration (SA-SPTR). SA-SPTR is designed based on the Network Simplex Method (NSM) and Sensitivity Analysis (SA) techniques to provide a comprehensive and low-cost link failure healing process. NSM is used to derive the shortest paths for each node, while the use of SA can greatly reduce the effort of unnecessary recomputation of the SPT when network topology changes. The numerical results show that the proposed algorithm has least time complexity.