Provision of alternative communications paths in a communications network

摘要

A method of processing data for computing alternative paths in an optical network (10, 40) including making a list of groups (12, 14, 16, 18, 20, 22, 24, 26) that comprise links wherein the links in a group share a risk of being affected by the same fault, comparing each group (12, 14, 16, 18, 20, 22, 24, 26) with other groups (12, 14, 16, 18, 20, 22, 24, 26) in the list to determine whether each group includes the same links as another group, and deleting the groups (16, 26, 20, 22) that comprise links which are a subset of the links in another group.