Algorithmic and Optimization Strategies for Efficient Routing and Resource Management in Advanced Elastic Optical Networks

ABSTRACT In response to the rapidly increasing demand for higher bandwidth and the necessity for more flexible and efficient resource allocation, elastic optical networks have emerged as a promising solution for next‐generation high‐capacity optical communication systems. These networks leverage flexible spectrum management techniques, such as flexible grid and adaptive modulation formats, to enhance spectral utilization and support fluctuating traffic demands. However, the design and operation of these networks pose significant challenges, particularly in the context of the constrained routing and spectrum assignment (C‐RSA) problem, which involves determining optimal routing paths and spectrum allocations while satisfying various constraints such as spectrum contiguity, continuity, and nonoverlapping requirements. In this paper, we introduce an integer linear programming formulation for the C‐RSA problem and conduct a polyhedral investigation of the associated polytope. We describe several valid inequalities, present necessary and sufficient conditions under which these inequalities are facet‐defining, and then discuss the related separation problems. Based on these results, we develop a Branch‐and‐Cut algorithm to solve the problem. Additionally, we present computational results that demonstrate the effectiveness of our approach using various instances. Moreover, we compare our approach with existing methods from the literature as well as various state‐of‐the‐art MILP solvers.