Bandwidth granularity adaptation for multipath provisioning in elastic optical OFDM-based networks

In this paper, we consider the impact of spectrum fragmentation along the optical single-/multi-path routing transmission on the efficiency of the elastic optical networks. Using O-OFDM multicarrier transmission as a promising technique makes it possible to choose just an adequate portion of available spectrum to satisfy the requested capacity. This involves focusing on the work to reduce the fragmentation effects by dynamically updating and controlling the minimum bandwidth allocation granularity. We investigate the concept of “minimum bandwidth allocation granularity adaptation” to replace using one fixed minimum bandwidth granularity allocation to serve the light path requests over multipath networks. We adopt a dynamic adaptation mechanism that is proportional to the optical link/path bandwidth fragmentation status. Simulation results show that the minimum bandwidth granularity dynamic adaptation based on the optical path fragmentation status offers improved performance over fixed minimum bandwidth allocation granularity with respect to the bandwidth blocking probability, the number of path splitting, and the throughput.