L-Grow: A Heuristic Algorithm for P-Cycle Optimization Based on Optical Network

As optical networks present both broadband and complication trends, network reliability is an important consideration in designing optical transport networks. For the improvement of network operation status and reliability, there are a lot of research on network protection and recovery strategy. Although these algorithms can achieve better theoretical results, it is very easy to have too many P-Cycles, too much construction cost and poor performance. This paper presents a heuristic algorithm L-Grow for P-Cycle optimization construction. This algorithm optimizes the Grow algorithm, fully considers the actual cost of constructing P-Cycle and the maximum protection capability of P-Cycle. It improves the actual quality of P-Cycle by introducing the ratio parameter T of the maximum protection capability to the actual cost of P-Cycle, chooses K P-Cycles before T value to complete the screening of intermediate cycles, restricting the number of P-cycles constructed by the method of cross-merging of cycles, improves the actual performance of P-Cycles and reduces the pressure of network operation. The results show that the L-Group algorithm effectively reduces the number of P-Cycles, improves the maximum protection capability and cost efficiency of P-Cycle, reduces the pressure of network management, and improves the utilization rate of resources and network reliability.