Hybrid Static−Dynamic Link Weighting for Blocking Probability Reduction in Elastic Optical Networks

In Elastic Optical Networks (EON), the topology structure causes some links to bear more traffic load than others and act as traffic highways. The concentration of traffic on these links, especially in dynamic traffic conditions, leads to increased spectral fragmentation, bottlenecks, and ultimately increased request blocking rates. In this paper, an algorithm called Hybrid Link Weighting(HLW) is proposed for uniform load distribution and management of high-use links in EON and SDM-EON networks. In the proposed algorithm, each link is assigned a combined weight that includes two static and dynamic components. The static component measures the criticality of the link based on the impact of its removal on the network DBR, while the dynamic component evaluates the current state of the link based on the load and fragmentation index (Golden Metric). The final weight of each link is obtained from the linear combination of these two components with coefficients α and β (assuming α + β =1). Simulation results on standard topologies show that the appropriate choice of coefficients (especially α=0.25 and β=0.75) leads to a significant reduction in the blocking rate compared to conventional methods. The proposed algorithm, by simultaneously considering the topological criticality of links and their instantaneous utilization status, is able to prevent traffic concentration on highway links and improve the overall network efficiency.