Ultra high speed calculation method for link bandwidth design considering failures

This paper proposes an ultra high speed calculation method for a link bandwidth design considering failures by using Linear Programming (LP). Our previous study has already proposed the link bandwidth design method by using LP, however the previous method takes quite a lot of calculation time in a large network because of the LP calculation. As the network size becomes larger, the numbers of constraints and the number of variables used in the LP calculation increase, so the LP calculation time increases significantly. The proposed method adds a step that reduces constraints and variables that are expected not to influence the LP calculation result by a heuristic method before LP calculation for the speed-up of the calculation. Simulation results show that the proposed method achieves less 1/200 calculation time shortening with an increase of only thin several percent in the total design bandwidth amount in COST266 Network where the number of nodes and links is 26 and 154 respectively, compared with the previous method. That is, the proposed method is very excellent in not only speed-up of the LP calculation but also the accuracy of calculation result.