Dynamic Crosstalk-Aware Routing, Modulation, Core, and Spectrum Allocation for Sliceable Demands in SDM-EONs

Elastic optical networks (EONs) will not be able to satisfy the ever-increasing demand of the next-generation Internet applications. Thus, space-division multiplexing (SDM) technology is introduced to increase the fiber capacity and incorporate multiple EONs (SDM-EONs), specifically through implementing multi-core fibers (MCFs). Inter-core crosstalk (XT) is the fundamental issue in MCF, leading to lower utilization and lower optical signal quality. Due to the presence of significant XT, the traditional resource allocation problem in SDM-EONs needs to incorporate dynamic XT values. This paper describes a comprehensive solution that incorporates the XT constraint during routing, modulation, core, and spectrum allocation in the software-defined networking controller. First, we present a dynamic XT-aware routing (XTAR) algorithm with two policies in which link costs are dynamically calculated based on the XT effect and length of the links. Next, we introduce a new XT-aware bandwidth-slicing resource allocation approach that considers both XT limitations and simultaneously addresses blocking of large demands due to fragmentation and optical reach. Extensive simulations on several well-known network topologies reveal that the average request blocking for both the proposed policies significantly outperforms traditional shortest-path based benchmark.