In All-optical Network Fast Fault Location Monitoring Research

With the development of Internet technology, Internet carrys more and more types of business, which is also increasing. All-optical network based on WDM technology can meet the demands of network bandwidth and QoS. However, optical network is very fragile, and once the fiber link fails, it will cause a lot of data loss and service interruptions. Therefore quickly identify the fiber link failure becomes extreamly important. Only if the fiber link failure can be quiakly monitored and located, upper layer can accordingly adjusts routing protocol so that to timely recover data transmission by transferring data on the failed link to other link.The first chapter summarizes the designing idea of m-trail and its benefits, and compares m-trail and other types of optical network link fault location solution, as well as describes the existing scheme of designing m-trail to locate single link fault.Because there are various forms of failure in actual network, the second and third chapter respectively research on the application of m-trail used in SRLG fault location and dual-links fault location. With regard to fault location for SRLG, the second chapter talks about the designe of distributing m-trail heuristic algorithm. This algorithm weights link cost with the product of node degrees and the reciprocal of link costs, which makes it possible to take as much as routing into account, together with the impact of link costs on monitor cost. Besides, the algorithm extends the m-trail with a probabilistic model, which randomly selects the next hop, so it successfully increases its solution space. The third chapter focuses on the analysis of simultaneous failure of two fiber links in optical networks, and accordingly proposes an ILP model with the charcteristics of m-trail to locate this kind of failure, and then simulates the algorithms and analyzes their performances.Combining the advantages of m-trail and monitoring tree, this paper proposes an m-forest plan to realize fast link fault location, as well as its corresponding ILP model. Based on the analysis of the ILP modle, a new heuristic algorithm is proposed. The algorithm first obtains the m-trail structure by the means of useful m-trail design, and then constructs the m-forest by merging the m-trail into several m-trees under certain constraints. The experiment result proves that the algorithm has better performance compared to m-trail and m-tree scheme.Finally, there is a sum of this paper。...