Virtual topology design and method of virtual topology design apparatus

摘要

PROBLEM TO BE SOLVED: To provide a virtual network topology designing apparatus capable of ensuring reachability between each of nodes of an upper layer even when a fault occurs in a physical link or node of a lower layer.;SOLUTION: The virtual network topology design apparatus 10 includes: a logic topology designing means 12 for designing a logic topology; a lower layer path allocating means 13 for allocating a lower layer path to the designed logic topology; a reliability evaluating means 24 for evaluating whether the logic topology satisfies a reliability condition showing a condition that ensures reachability between each of nodes having a transfer function of an upper layer, when a fault occurs in a physical link of the lower layer; and a lower layer path accommodation change designing means 23 for designing an accommodation change of a lower layer path so as to satisfy the reliability condition by changing a node that passes through the lower layer path without changing an end point of the allocated lower layer path, when the logic topology does not satisfy the reliability condition.;COPYRIGHT: (C)2008,JPO&INPIT