ISRS-Enhanced PLI-Aware Routing for Multi-Band Elastic Optical Networks

With the growing demand for high-bandwidth applications, traditional optical networks are reaching their capacity limits. Multi-band elastic optical networks (MB-EONs) have emerged as a cost-effective and promising solution to enhance spectral efficiency by utilizing spectrum slots across multiple bands beyond the C-band. However, the performance of MBEONs is significantly affected by physical layer impairments (PLIs), including amplified spontaneous emission (ASE), nonlinear interference (NLI), and inter-channel stimulated Raman scattering (ISRS), which complicate dynamic resource allocation and degrade the quality of transmission (QoT). To address these challenges, we propose an ISRS-Enhanced PLI-Aware (IE-PLIA) routing algorithm for MB-EON resource allocation, explicitly accounting for PLIs under the influence of ISRS. Unlike prior approaches, IE-PLIA dynamically adjusts routing costs based on link conditions, self-channel interference (SCI), and cross-channel interference (XCI) variations induced by ISRS. Furthermore, we investigate the network performance under various traffic load conditions to determine when transitioning from single-band to multi-band EONs becomes advantageous. Our results show that IE-PLIA significantly lowers the blocking probability, achieving a 60% reduction compared to the benchmark algorithm in the Pan-European network at 2000 Erlangs.