Energy-Aware Forwarding Strategy for Metro Ethernet Networks

Energy optimization has become a crucial issue in the realm of ICT. This paper addresses the problem of energy consumption in a Metro Ethernet network. Ethernet technology deployments have been increasing tremendously because of their simplicity and low cost. However, much research remains to be conducted to address energy efficiency in Ethernet networks. In this paper, we propose a novel Energy Aware Forwarding Strategy for Metro Ethernet networks based on a modification of the Internet Energy Aware Routing (EAR) algorithm. Our contribution identifies the set of links to turn off and maintain links with minimum energy impact on the active state. Our proposed algorithm could be a superior choice for use in networks with low saturation, as it involves a tradeoff between maintaining good network performance and minimizing the active links in the network. Performance evaluation shows that, at medium load traffic, energy savings of 60% can be achieved. At high loads, energy savings of 40% can be achieved without affecting the network performance

Routage efficace en énergie pour les réseaux Carrier Ethernet

The reduction of energy consumption is a major concern for Telecom operators and Internet Service Providers (ISPs). This thesis addresses the problem of energy efficiency in the wired communication networks using Ethernet based technology. We study the most relevant models of energy-aware routing which are Carrier-grade Ethernet compliant. For every routing model, we present mathematical formulation as an exact method based on linear programming. In addition, we propose a set of heuristic algorithms suitable for large-sized networks. In order to better understand the possible ways to limit energy consumption in Metro Ethernet systems, the first part of this thesis is to survey and classify the main approaches related to energy saving on IP networks that could be adapted to Metro Ethernet systems. The second part is devoted to the implementation of new energy-efficient routing models and algorithms for Carrier Ethernet networks. We present two models which are compliant with SPB (Shortest Path Bridging protocol, IEEE 802.1aq). The first model can be categorized as a topology oriented model that ignores the network traffic in sleeping decision. Whereas the second, can be categorized as traffic oriented model, that takes into account the network traffic matrices in sleeping decision. Afterwards, we deal with energy aware routing with SDN (Software Defined Network) approach. Finally, we evaluate the impact of our algorithms on the most relevant network performance metrics such as the network connectivity, the average paths length, the average traffic load, network reliability and the fairness of traffic distribution. The experiments on several realistic network topologies showed that our models could achieve a significant amount of energy saving while maintaining an acceptable network performance.Cette thèse aborde la problématique de la consommation d'énergie dans les réseaux filaires et plus particulièrement dans les réseaux métropolitains qui utilisent Ethernet au niveau du transporteur. Dans cette thèse, nous développons plusieurs approches avec intelligence logiquement centralisée afin d’endormir les éléments redondants du réseau. Pour modéliser le problème, nous présentons différentes formulations à l’aide de programmation linéaire. Nous avons étudié deux approches d’ingénierie verte avec le protocole SPB IEEE 802.1aq de réseau cœur Ethernet. Egalement, nous avons étudié une ingénierie verte avec une architecture basée sur les réseaux programmables SDN. Ainsi, nous étendons notre étude pour calculer deschemins économes et fiables contre la défaillance du nœud ou lien

Energy Saving in Carrier-Grade Networks: A Survey

International audienceEnergy consumption of large-scale networks has become a primary concern in a society increasingly dependent on information technology. Novel solutions that contribute to achieving energy savings in wired networks have been proposed to mitigate ongoing and alarming climate change and global warming. A detailed survey of relevant power-saving approaches in wired networks is presented here. We give a special focus on carrier-grade networks. At first we perform a comprehensive study of communication infrastructures regarding energy saving. Then, we highlight key issues to enable green networks, ranging from network design to network operation. After that, we present the major contributors to power consumption in wireline networks. Afterwards, we survey, classify, and compare the main energy-aware methods and mechanisms that are the most appropriate for improving the energy efficiency of carrier-grade networks

Study of Energy Saving in Carrier-Ethernet Network

International audienceEnergy saving is a really interesting topic in today's networks. Indeed Information and Communication Technologies (ICT) systems are energy greedy, they require more and more energy and as energy is more and more expensive we seek to save it. Accordingly, energy saving has recently received considerable attention, as a promising approach for delivering ICT services with environmentally conscious use of technology by implementing energy aware strategies in networks infrastructures which lead to improve network resources utilization. Thus this paper addresses the issue of energy consumption in telecommunication networks and especially in Carrier-Ethernet networks. We review and describe relevant works currently proposed for energy-efficient operation of wired network infrastructure. Besides surveying some of the different technical issues that researchers are currently facing to reduce the energy consumption in networking, this paper identifies some of the remaining key research challenges that arise when such energy-saving techniques are extended for use in Carrier Ethernet networks

Equal Cost Multiple Path Energy-Aware Routing in Carrier-Ethernet Networks with Bundled Links

International audienceThe reduction of operational expenditure has become a major concern for telecommunication operators and Internet service providers. In this paper, we propose an energy aware routing (EAR) in Carrier Ethernet networks operating with Shortest Path Bridging (SPB) protocol with equal cost multi-path (ECMP). Since traffic load has no influence on power consumption of Carrier Ethernet network elements, the conventional solution to reduce power consumption is to find the maximal set of network elements that can be turned off/on so that the network performance is not deteriorated. To tackle this optimization problem, we propose an exact method based on Mixed Integer Linear Programming (MILP) formulation, called SPB energy-aware routing (SPB-EAR). Since SPB-EAR is proved to be NP-hard, we present two heuristics algorithm suitable for large-sized networks, called Green SPB (G-SPB) and Fast Greedy SPB (FG-SPB). In this work, we consider that a connection between two nodes is represented by bundled link consisting of multiple cables. Experimentations on four realistic network topologies show that G-SPB and FG-SPB can save almost as much power consumption as SPB-EAR

Energy-Aware Routing in Carrier-Grade Ethernet using SDN Approach

International audienceSoft-Defined Networking (SDN) is a new approach that enables operators to easily manage all the network elements. In this paper, we address the problem of energy-aware routing in SDN-based carrier-grade Ethernet networks. Our approach is based on turning off network nodes and links to reduce energy consumption, while respecting the rule space capacity for each Openflow switch, and maintaining an allowable maximum link utilization. The problem of identifying the optimal set of network elements to be turned off is NP-hard. We first present an exact model based on an Integer Linear Programming formulation for the problem. Then, we describe a set of first-fit heuristic algorithms suitable for large-sized networks. The exact and heuristic approaches are tested on SNDlib-based instances. Experimentations show the efficiency of both exact and heuristic methods for different network topologies. In particular, our heuristic algorithms are able to achieve a good balance between energy consumption, resource utilization, and network performance

Two Node-Disjoint Paths Routing for Energy-Efficiency and Network Reliability

International audienceCarrier grade networks are in general over-dimensioned in order to protect against network resource failures and to handle probable traffic peaks. Such network design exhibits non-negligible energy waste. As well known, during network operation, the traffic load varies remarkably over day hours. Typically, a significant amount of energy saving can be achieved by turning off redundant and underutilized resources. Ensuring a sufficient level of reliability while taking into account energy saving objective is a very challenging task. In this paper, we study the multi-commodity reliable network design for carrier Ethernet networks. Each traffic demand is routed along one working path, and a corresponding backup path computed considering dedicated protection scheme. The primary and backup path must be node-disjoint. We also assume that the links of the carrier grade networks are made of multiple physical cables called bundles. We propose an exact method based on an Integer Linear Programming (ILP) formulation for the two node-disjoint paths with energy-aware routing (TNDP-EAR) problem. The studied problem is known to be NP-hard. In order to solve it efficiently, we propose a heuristic-based algorithm called GreenTNDP. Preliminary experimental results show the effectiveness of our algorithms to solve the problem