Patent ID: 7493041

Claim:
An optical path re-arrangement method for re-arranging optical paths in an optical communication network comprising a plurality of routers, a plurality of optical switches, optical fiber connecting the routers and optical switches or connecting the optical switches, and a management device, comprising the steps of: obtaining a first evaluation value by evaluating a packet loss amount when changing the optical path arrangement by means of a one-stage shift; recording said first evaluation value in a storage device; selecting randomly, as a first-order shift optical path one optical path group produced by dividing an optical group that is to be changed into two when changing the optical path arrangement by means of a two-stage shift of a first order shift and a second-order shift and then making the other optical path group a second shift optical path; obtaining a second evaluation value by evaluating a packet loss amount when changing the optical path arrangement by means of the two-stage shift; and comparing said second evaluation value with said first evaluation value and, when said second evaluation value is smaller than said first evaluation value, substituting said first evaluation value with said second evaluation value and then recording said first evaluation value and said first and second-order shift optical paths in the storage device, wherein a processing termination condition that is pre-recorded in the storage device is read, the step for selecting, the step for obtaining a second evaluation value and the step for comparing are repeated until said processing termination condition is satisfied, and said processing termination condition is set as the time for performing the processing of said management device or the number of the times that the step for comparing said second evaluation value with said first evaluation value is repeatedly implemented.