Protocol Enhancements for 'Greening' Optical Networks

For the last decade, many research efforts have been made in energy efficiency in Information and Communication Technologies (ICT). To reduce the energy consumed by optical transport networks, one option is to switch off a certain number of optical systems according to the amount of transported traffic. Consequently, dynamic power management of optoelectronic devices and link sleep-modes were proposed; these capabilities quantitatively optimize the power requirements and the available bandwidth of the network as a whole. This article firstly presents the enhancements embedded in GMPLS based protocols enabling the control of power in the optical devices, and then analyzes the impact of controlling the energy consumption of optical switching equipments on the network daily consumption. Finally the on-going activities in specific standardization working groups for "greening the network are presented, jointly with their proposals to improve the energy efficiency of future optical networks.