Protocol enhancements for “greening” optical networks

Abstract

The last decade has spurred a number of research efforts around 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‐mode approaches have been proposed; these capabilities quantitatively optimize the power requirements and the available bandwidth of the network as a whole. This paper presents enhancements embedded in Generalized Multiprotocol Label Switching (GMPLS)‐based protocols enabling power control in optical devices, and then analyzes the impact of controlling the daily energy consumption of optical switching equipment in the network. We also present ongoing activities in specific standardization working groups for “greening the network” along with their proposals to improve the energy efficiency of future optical networks. © 2013 Alcatel‐Lucent.

Optimization/simulation-based risk mitigation in resilient green communication networks

“…This type of energy profile is widely reported, also in the resilience context (Xia et al, 2011;Jirattigalachote et al, 2011;Bolla et al, 2011b;Bao et al, 2012;Chiaraviglio et al, 2013;Morea et al, 2013;Zu et al, 2013;Viswanath et al, 2014). While a proportional energy usage for various elements is desirable, the problem is that the fixed switch on cost E 0 is not zero and it is not clear whether it can be reduced to zero.…”

“…A typical approach is to minimize energy usage with (M)ILP formulations such as done by Morea et al (2013), who optimize Routing and Wavelength Assignment (RWA) jointly with 1:1 dedicated protection, and solve the optimization task by a commercial solver (IBM ILOG CPLEX). Likewise, Liu et al (2013) present algorithms for energy-efficient routing of connections protected with shared backup paths, so that the shared spare resources are put to sleep.…”

Energy-efficiency versus resilience: risk awareness view on dimensioning of optical networks with a sleep mode

“…While generally the sleep mode mechanisms are not present in contemporary network devices, some attempts to include them in protocol suites exist. For instance, Morea et al [44] propose enhancements in the Generalized MultiProtocol Label Switching (GMPLS) control plane protocols. Additionally, documents have been produced in the Internet Engineering Task Force by Eman (a working group on energy management, established in 2009) to provide the management plane with the necessary ontology to represent data useful in energy-aware networks, taking into account the sleep mode [22,52].…”

“…Additionally, documents have been produced in the Internet Engineering Task Force by Eman (a working group on energy management, established in 2009) to provide the management plane with the necessary ontology to represent data useful in energy-aware networks, taking into account the sleep mode [22,52]. Energy profiles supporting our approach and adapted in the design and optimization of optical networks, sometimes with resilience provisioning, are reported in [5,9,13,14,36,44,56,67]. While assuming the most common fixed + proportional (f + p) energy profile for single elements, the total energy usage for the whole network has the concave character as a function of the summarized network load [36,67].…”

“…Many papers provide optimization formulations with f + p energy profiles; however, to our knowledge, none of them propose the use of Yaged's heuristic. A typical approach in the context of resilient energy-efficient networks is to minimize energy usage with mixed integer linear programming (MILP) formulations such as in [44], where routing and wavelength assignment (RWA) is optimized jointly with 1:1 dedicated protection, and then the optimization formulation is solved by a commercial solver. For instance, Liu et al [38] present algorithms for energyefficient routing of connections protected with shared backup paths, so that the shared spare resources are put to sleep.…”