Blocking-triggered Defragmentation Mechanism Based on the Selected Path for Elastic Optical Network.

A blocking-triggered defragmentation mechanism based on the selected path (SP-D) is proposed to solve spectrum fragments in elastic optical networks (EONs). The proposed mechanism analyzes the arriving traffic requirement as well as the current spectrum condition, and then takes the effectiveness and the complexity of spectrum defragmentation into consideration simultaneously. When service blocking is detected, a path from source node to destination node is selected according to the proposed policy and then the spectrum reallocation is performed sequentially based on the selected path to ease the blocking situation. Theoretical analysis and numerical simulation results show that compared with the previous mechanisms, the proposed SP-D mechanism can reduce the network latency as 7.67% and decrease the bandwidth blocking probability (BBP) as 5.3%, respectively.