Ward Van Heddeghem

Learn More
The evaluation of and reduction in energy consumption of backbone telecommunication networks has been a popular subject of academic research for the last decade. A critical parameter in these studies is the power consumption of the individual network devices. It appears that across different studies, a wide range of power values for similar equipment is(More)
One of the main challenges for the future of information and communication technologies is the reduction of the power consumption in telecommunication networks. The key consumers are the home gateways at the customer premises for fixed line access technologies and the base stations for wireless access technologies. However, with increasing bit rates, the(More)
Information and Communication Technology (ICT) devices and services are becoming more and more widespread in all aspects of human life. Following an increased worldwide focus on the environmental impacts of energy consumption in general, there is also a growing attention to the electricity consumption associated with ICT equipment. In this paper we assess(More)
Reasonably accurate reference power consumption values are required for any work that evaluates power consumption in telecommunication networks. Many existing works provide or use optimal power rating (W/Gbps) values, i.e. the power rating achieved for the maximum capacity of the system, with the shared relative overhead thus being the smallest. In this(More)
Energy-efficiency and resiliency are two well-established research topics in optical transport networks. On the other hand, their overall objectives (i.e., power minimization and resourceutilization/availability maximization) are in contrast. In fact, provisioning schemes optimized for best resiliency performance are in most cases not energy-efficient in(More)
Low carbon footprint energy sources such as solar and wind power typically suffer from unpredictable or limited availability. By globally distributing a number of these renewable sources, these effects can largely be compensated for. We look at the feasibility of this approach for powering already distributed data centers in order to operate at a reduced(More)
As one of the first worldwide initiatives provisioning ICT (Information and Communication Technologies) services entirely based on renewable energy such as solar, wind and hydroelectricity across Canada and around the world, the GreenStar Network (GSN) is developed to dynamically transport user services to be processed in data centers built in proximity to(More)
While telecommunication networks have historically been dominated by a circuit-switched paradigm, the last decades have seen a clear trend towards packet-switched networks. In this paper we evaluate how both paradigms perform in optical backbone networks from a power consumption point of view, and whether the general agreement of circuit switching being(More)
Energy saving in telecommunications networks has become a well established topic in the research community. We look at the electrical and optical layers of IP-over-WDM networks, and present a list of evaluation criteria for the Energy-Aware Adaptive Routing Solutions (EA-ARSs) from the perspective of a network operator. Furthermore, we briefly explain the(More)
This paper explores the problem of virtual machine (VM) allocation in a network of cloud server facilities which are deployed in different geographical areas. Each cloud server facility is connected to the conventional power grid network and in addition it is supported by an attached renewable energy source (RES). We address the problem of energy-efficient(More)