Nonlinear Lagrange relaxation based QoS routing revisited

The development of efficient quality of service (QoS) routing algorithms in a high-speed networking or the next generation IP networking environment is a very important and at the same time very difficult task due to the need to provide divergent services with multiple QoS requirements. Recently, a heuristic algorithm H_MCOP, which is based on a nonlinear Lagrange relaxation (NLR) technique, has been proposed to resolve the contradiction between the time complexity and the quality of solution. Even though H_MCOP has demonstrated outstanding capability for finding feasible solutions to the multi-path constrained (MCP) problem, it has not exploited the full capability that an NLR-based technique could offer. In this paper, we propose a new NLR-based heuristic, in which the search process is interpreted from a probability perspective. Simulation results indicate that, in comparison with H_MCOP, the proposed heuristic can achieve a significant performance improvement when it is used as a basic step for solving more complicated QoS routing problems.