Abstract
Despite the significant degree of technological maturity reached by large-scale optical transmission infrastructures, new critical issues are emerging as side effects associated to their energy consumption, environmental impact and related costs, now accounting for an important part of the networks' operational expenditures. To face this problem, we propose a single-stage routing and wavelength assignment scheme, based on several network engineering extensions to the Generalised Multi-Protocol Label Switching (GMPLS) control plane protocols, mainly Open Shortest Path First, with new composed metrics and information transport facilities. It is structured according to a simple multi-objective optimisation approach aiming at containing the network's energy consumption and ecological impact while balancing the overall load and maintaining an acceptable connection demand satisfaction rate. The proposed solution is able to operate effectively in wide area wavelength routing scenarios, where multiple heterogeneous equipment, ranging from pure photonic to opaque routing/switching, amplification and regeneration devices are deployed in a GMPLS-empowered network. Copyright (c) 2014 John Wiley & Sons, Ltd.