| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To facilitate optimum route calculation for point-to-multipoint paths, applied with a Fast Reroute system, for speeding up recovery from single-node failure. <P>SOLUTION: Routes of standby paths to respective adjacent link pairs in a network are previously found (S21) and then fixed, and an integer programming method is used to find in-use point-to-multipoint path routes (S22) minimizing the total route cost of in-use paths and a standby path group to the respective link pairs that the in-use paths pass and the route cost (S23). Then routes of the in-use point-to-multipoint paths are fixed, and the integer programming method is used to find routes (S25) of a standby path group minimizing the total route cost and the route cost (S26). The route calculation processings are repeated alternately (S24, S27) until the degree of improvement in which the route cost becomes below a predetermined threshold value. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
