In this paper, a novel method is proposed to address the problem of designing virtual topology over wavelength division multiplexing （WDM） networks under bandwidth demand uncertainties. And a bandwidth demand model ...In this paper, a novel method is proposed to address the problem of designing virtual topology over wavelength division multiplexing （WDM） networks under bandwidth demand uncertainties. And a bandwidth demand model under uncertainties is presented. The optimization goal of virtual topology design is defined as minimizing the maximum value amongp percentiles of the bandwidth demand distribution on all Hght-paths. Correspondingly, we propose a heuristic algorithm called an improved decreasing multi-hop logical topology design algorithm （ID-MLTDA） that involves with a degree of uncertainties to design virtual topology. The proposed algorithm yields better performance than previous algorithms. Additionally, the simplicity and efficiency of the proposed algorithm can be in favor of the feasibility for topology design of large networks.展开更多
Because of no strict expression of calculating call blocking probability （CBP） in the solution procedure of virtual-path bandwidth allocation problem, the process of calculating bandwidth through CBP and traffic loa...Because of no strict expression of calculating call blocking probability （CBP） in the solution procedure of virtual-path bandwidth allocation problem, the process of calculating bandwidth through CBP and traffic load adopts the iteration algorithm in common, which is an inverse process of calculating CBP through traffic load and bandwidth. It limits computing speed by a long way because of including recursion. An approximate algorithm of bandwidth is presented. We compare the performance of this algorithm with that of another classical algorithm and conclude that the former makes a great increase in speed with little error about 2 %.展开更多
基金Supported by the National Natural Science Foundation of China (No.90604002)Program for New Century Excellent Talents in University (No. 05-0807).
文摘In this paper, a novel method is proposed to address the problem of designing virtual topology over wavelength division multiplexing （WDM） networks under bandwidth demand uncertainties. And a bandwidth demand model under uncertainties is presented. The optimization goal of virtual topology design is defined as minimizing the maximum value amongp percentiles of the bandwidth demand distribution on all Hght-paths. Correspondingly, we propose a heuristic algorithm called an improved decreasing multi-hop logical topology design algorithm （ID-MLTDA） that involves with a degree of uncertainties to design virtual topology. The proposed algorithm yields better performance than previous algorithms. Additionally, the simplicity and efficiency of the proposed algorithm can be in favor of the feasibility for topology design of large networks.
基金This project was supported by National Natural Science Foundation of China (69972015) Guangdong Provincial NationalScience Foundation (31391) .
文摘Because of no strict expression of calculating call blocking probability （CBP） in the solution procedure of virtual-path bandwidth allocation problem, the process of calculating bandwidth through CBP and traffic load adopts the iteration algorithm in common, which is an inverse process of calculating CBP through traffic load and bandwidth. It limits computing speed by a long way because of including recursion. An approximate algorithm of bandwidth is presented. We compare the performance of this algorithm with that of another classical algorithm and conclude that the former makes a great increase in speed with little error about 2 %.
