Experimental evaluation of the link cost impact in OSNR-based IRWA algorithms for GMPLS-enabled translucent WSON

This article addresses the dynamic provisioning of optical connections within a GMPLS-enabled translucent wavelength switched optical network with sparse 3R regenerators. To this end, an OSNR-based IRWA algorithm computes routes that aim at satisfying both restrictions: the wavelength continuity constraint and adequate end-to-end optical signal quality. If either constraint cannot be satisfied, the sparse 3R regenerators placed throughout the network may be employed. Given the fact that 3R regenerators are considered a cost-expensive network resource, the IRWA algorithm is devised to optimize/minimize the utilization of available 3R regenerators when computing paths. This is accomplished through a cost-model function in which two metrics are defined, namely, the network link cost and the node regenerator cost. Thereby, the IRWA algorithm computes shortest paths considering those costs while fulfilling the above constraints. In this work, we present and evaluate the performance of the devised algorithm through varying the link costs. The numerical results are compared in terms of the connection blocking probability, which are experimentally obtained within the ADRENALINE testbed. For the sake of completeness, several scenarios with a different number of 3R regenerators are evaluated for the considered Japanese network topology.