Performance of Defragmentation Approach Based on Route Partitioning in 1+1 Protected Elastic Optical Networks

Spectrum fragmentation suppresses spectrum usage in survivable elastic optical networks (EONs). Survivable EONs with full and quasi-1+1 protected services require an effective spectrum defragmentation approach. Full-1+1 path protection ensures dependability without disrupting traffic when the backup route cannot be reallocated. If a working path fails while its backup route is being moved, the reliability of a service that provides full-1+1 protection goes down. To defragment them, network operators must carefully study EONs with full-1+1 and quasi-1+1 protected lightpaths. In 1+1 protected EONs with full and quasi-1+1 protected services, route partitioning-based defragmentation reduces spectrum fragmentation and blocking probability. Retuning interference arises when a full-1+1 protected lightpath cannot be returned to fill up a gap created by a terminated lightpath owing to interfering from another lightpath that stops it from retuning farther. The introduced defragmentation approach minimizes this interference. A simulation study demonstrates the efficacy of the presented defragmentation approach with route partitioning.