The Research On The Survivability Of Multilayer Network Anti-N Fibers Failure

With the rapid growth of communication traffic，the traditional transmissionnetwork is faced with the unprecedented challenges. And the Transmission network hasundergone tremendous changes in business, traffic patterns, and operational aspects andso on. Therefore, the research and application on wavelength and routed OpticalTransport Network (OTN) become very important issues, and the research aboutsurvivability is one of the important issues. Considering in the actual optical network,due to various failures may result in multiple physical fiber breaks (failure)simultaneously. Therefore all the traffic in the optical path is bound to failure. And Inthe case, this will caused serious distress to the traffic communications. Therefore, inview of the above situation, the survivability about MLN (multi-layer optical network)to deal with the failure of N physical is the main research object in this dissertation.In this dissertation, the survivability on Multilayer optical network anti-N fibersfailure simultaneously is researched from two perspectives. The main content is asfollows:From the static perspective, explicit routing technology based on protection isresearched to deal with the failure of N fibers simultaneously. The core idea ispre-calculating the end-to-end work path resources and protection path resources. In thisdissertation, the multi-path algorithm,traffic protection technology, resource sharingtechnology and traffic grooming are integrated an algorithm named BER-MLS.Thealgorithm is proved by the simulation results that it can provide reliable protection forthe traffic and the resource utilization is10%higher than the existed algorithm.From the dynamic perspective, dynamic rerouting technology based on restorationis also researched to deal with the failure of N fibers simultaneously. This technology isnot preset the protection resource in advance for the traffic but to restore the trafficaccording to the network’s idle resources dynamically after failure. The recovery issueof the traffic in the multi-layered network is an NP-Complete problem. The previousrestoration technique cannot guarantee the completely restoration ability, just to providethe best-effort service. However, the purpose of the thesis is that it must insure the restoration of traffic as long as the residual network is still connectivity. The thesispresents an algorithm named BDR-MLS Based, which contains the work pathcomputation algorithm, reserved resources computing algorithm, dynamic restorationalgorithm. And the simulation results of the algorithm show that the algorithm canprovide reliable protection for all the traffic, and the consumption of network resource islower than the BDR-MLS algorithm, but only needs to be improved in time efficiency.The simulation of the proposed algorithm is implemented via C++programmingand QT GUI.And the failure simulation software about dealing with the fibers failure isimplemented. Finally, based on the summarization of the obtained results, some aspectsof research for future are given.