电力光通信网中基于P圈的多播业务保护算法

P-Cycle Based Protection Algorithm for Multicasting Services in Electric Optical Network

为解决电力光通信网中多播业务的链路保护问题,提高电力光纤通信网的波长利用率,降低阻塞,提出了一种基于P圈（preconfigured cycle,P-cycle）的保护算法以实现电力多播通信业务故障的保护。基于电力光通信网中的多播业务需求,改进Prim算法生成与多播请求对应的优化多播树,以此为基础设计了启发式P圈构造算法将多播树的目的节点连接为圈以保护整棵多播树;针对保护资源利用效率问题,分析了P圈的复用条件,通过复用网络中配置的P圈以提高波长利用率;为降低阻塞,在生成多播树和P圈时采用了一种容量均衡策略以实现对链路负载的均衡。仿真结果表明,与已有哈密顿P圈和流P圈保护方案相比,所提算法能够显著降低电力通信网的冗余度和阻塞率,且在多播规模较小时有最佳的保护性能。

In order to solve the problem of link protection for multicast services and improve wavelength utilization ratio in electric optical communication networks,a protection algorithm based on preconfigured cycle,namely p-cycle,is presented to protect the multicast communication services with link failure scenario in this paper.Based on analyzing the multicast services in electric optical communication network,an improved Prim algorithm is used to generate optimized multicast tree corresponding to multicast request.Based on this,a heuristic p-cycle generation algorithm is designed to connect destination nodes of the multicast tree to form a cycle to protect entire tree.Aiming to improve utilization efficiency of wavelength,multiplexing conditions of the p-cycles are studied,and by multiplexing the p-cycles configured in the network,the wavelength utilization ratio could be raised.In order to decrease blocking probability of the network,a capacity balancing strategy is adopted to generate the multicast tree and p-cycles.Simulation results show that the proposed algorithm significantly reduces redundancy and blocking probability of the electric optical communication network compared to existing Hamiltonian p-cycle and flow p-cycle protection schemes and performs well when the multicast group size is small.