Physical Layer Impairment Aware Network Routing in Software Defined Optical Networks

Software-defined networks (SDNs) have been recognized as the next-generation networking paradigm that decouples the centralised control plane from the data forwarding elements. The multi-layer hierarchical SDN functionalities can be extended to control optical networks as a data plane which is called Software Defined Optical Network (SDON). In SDON, the logical control over and global access of all the optical components make the network routing more easier. In this paper, we propose the Physical-layer-impairment-aware Adaptive Routing (PAR) to address the routing problem in optical networks. The Physical Layer Impairments (PLIs) affect the connection establishment and degrades the quality of transmission. Thus, specifically, the distributed hierarchical control plane architecture is employed to minimize signalling delay, connection loss, quality of the signal, etc in large SDONs. We analysed our proposed methodology over two optical networks and compared its performance on the basis of blocking probability, connection congestion, and End to End (E2E) delay. The parameters are improved significantly as compared to the state-of-the-art OSPF routing protocol.