Efficient P-cycle combination protection strategy based on improved genetic algorithm in elastic optical networks

In order to address the problems of spectrum fragmentation and high redundancy of protection resources in the pre-configured cycle (P-cycle) protection, a genetic P-cycle combination protection strategy (GPCPS) based on improved genetic algorithm (IGA) is proposed for elastic optical networks. In GPCPS, an IGA is devised to optimise the basic cycles and find out an efficient P-cycle protection combination for protecting the whole optical topology. For alleviating the spectrum fragmentation, a P-cycle configuration strategy, named link spectrum partition and P-cycle configuration, is introduced to pre-configure the spectrum resource of P-cycles. Meanwhile, the least traffic priority and first fit algorithm based on spectrum resources usage and path length aware is designed to select working path effectively. Simulation results show that the proposed GPCPS can reduce the bandwidth blocking probability and improve the spectrum resource utilisation.