Study On Integrated Protection Method Of Optical Transport Network For High-speed Railway

As a high-speed railway infrastructure on the ground of the central nervous system,High-speed Optical Transport Network is taking the train operation in the process of information transfer.It includes state detection,fault diagnosis and the key information of dispatching command.The event of the fault interrupt will not only downgrade the high-speed railway operation control system,but also be likely to lead to termination of the train operation.Further,it might disturb the normal order of the operation of highspeed railway seriously.With the continuous increase of the carrying business types and capacity of high-speed railway optical transmission network,the reliability and real-time requirements of optical transmission network are improved constantly.Therefore,the protection and recovery technology to ensure the safety and stability of high-speed railway optical transmission network in operation has become a key research issue.This paper mainly studies the fault protection strategy of high-speed railway optical transmission network link.The research focuses on the protection and recovery technology of optical transmission network based on different link fault scenarios,which realizes the reliability and real-time requirements of different types of services and improves the survivability and recovery performance of the network in the case of link fault.1.This paper proposes a P-Cycle heuristic optimization algorithm L-Grow(LimitedGrow).This algorithm fully considered the ratio of actual cost and maximum protection ability of P-Cycle when evaluating P-Cycle protect quality.By defining the P-Cycle evaluation index protection cost efficiency T of tectonic process,first K middle ring choice,we use selective merge ring,strictly control the final structure the number of PCycle,which improving the quality of the protection of the P-Cycle.Simulation results of two network topologies,COST239 and Small Net,show that under the same link and node weight,the L-Grow algorithm is superior to the commonly used P-Cycle construction algorithm Grow in terms of P-Cycle number,average protection cost ratio and average prior efficiency.2.This paper proposes a P-MLP(Pre-Configured Multi-Level Protection)based on dual link fault Protection.The multi-fault scenarios are classified according to the network reliability and real-time requirements of high-speed railway optical transmission network.The protection method makes full use of the connectivity of the network topology to preconstruct the protection structure in the network topology,and uses the MLPRA(P-MLP Protection Routing Algorithm)routing algorithm to find the protection path for the fault link to complete the recovery.Simulation results of two network topologies,COST239 and Small Net,show that the protection resource allocation scheme is more flexible under the dual-link fault scenario.The protection structure can also protect the dual-link fault scenario with less resource cost,achieve nearly 100% recover effect on the fault link.In a word,it has great protection and recovery performance.