Study of Extended Cycle Restriction Based P-Cycle Construction Algorithm

P-Cycle protection technology is an important technology in optical network protection. This paper proposes a new P-Cycle construction algorithm ERPA (Extended cycle Restriction Based P-Cycle Construction Algorithm), which is based on the variance, mean and redundancy of unprotected working capacity on all candidate cycles. In the process of cycle expansion, the algorithm chooses the extended candidate cycle whose variance, mean and redundancy satisfy the conditions as the final candidate cycle of the current round, which can guarantee the quality of the extended cycle and limit the number of P-Cycle cycles that complete the protection; When the values of unprotected-links(UPL), the redundancy, mean and the parameter n satisfy the stop condition, the cycle expansion is stopped, so that the number of cycles and the cycle length can be effectively balanced. In the simulation process, the ERPA algorithm is simulated by using the COST293 European Optical Network (EON) topology model, and the performance under different n values is compared and analyzed. The simulation results show that ERPA algorithm needs fewer cycles, has higher protection capacity efficiency and lower total time consumption under the same resource and work capacity, which makes the proposed algorithm more feasible and effective.