Low-margin efficient power and spectrum assignment in elastic optical networks

In this work the spectrum and power allocation (SPA) trade-off in elastic optical network (EON) is discussed in terms of the residual margin and residual spectrum in real-time application, both terms refer to the normalization of the sum-power and sum-spectrum in the resource allocation, respectively. Realistic scenarios have been investigated using optical performance monitoring techniques to measure the quality of transmission (QoT). The SPA-EON problem is formulated and three algorithms finding improved performance-complexity trade-offs are proposed to solve it: i) an analytical method based on combinatorial optimization, namely SPA-CO algorithm, ensuring the optimal solution but with a high computational cost; ii) a sub-optimum low-complexity method based on distance adaptive transmission (DAT), namely SPA-DAT, and iii) an SPA algorithm based on the distributed Verhulst algorithm, namely SPA-V, which achieves good solutions under acceptable computational time. A bunch of metrics, including probability of success, sum-power, and allocated spectrum are evaluated for the three SPA algorithms. The SPA-V was proved to be promising in EON operation, achieving the best performance-complexity trade-off.