Performance of Hitless Defragmentation with Rerouting for Quasi $1+1$ Protected Elastic Optical Networks

This paper analyses the performance of the defragmentation scheme using path exchanging in 1+1 path protected elastic optical networks (EONs), which is intended to improve the traffic admissibility in the network. The defragmentation scheme reallocates spectrum slots of backup paths and allows to reroute the backup paths. The path exchange function of the defragmentation scheme makes the primary paths become the backup state while the backup paths become the primary. The simulation results show that the defragmentation scheme with path exchanging and rerouting outperforms the conventional schemes in terms of traffic admissibility and slot utilization.