Abstract: Aiming at improving network single link (node) failure fast recovery capability to enhance network survivability,a optimization methods is proposed based on LFA re-routing technology integrating the optimization of links weights on the base of PSO algorithm based on Simulated Annealing with minimal set cover algorithm based on bipartite graph.As LFA is hard to promise full coverage for all possible failure cases,PSO algorithm based on Simulated Annealing is used to optimize link weights for maximizing the numbers of LFA on the basis of original topology.Considering some networks is not also achieved full LFA failure full coverage after the optimization of link weights,then,the twice processes of supplement links is used to attain failure full backups.The experiment results show that this method proposed can not only keep all single link (node) failure with full LFA and enhance network survivability,but also effectively reduce the numbers of supplement links compared with the original topology.