We investigate the energy saving made possible by the network sharing approach, whereby all (or significant parts) of a network infrastructure are shared by different network operators. Our study reveals that in most European countries the amount of energy necessary to run mobile networks can be reduced by 35 to 60%.

2013 IEEE Online Conference on Green Communications is the 3rd edition of IEEE OnlineGreenComm conducted entirely online and dedicated to addressing the challenges in energy-efficient communications and communications for green technologies.

Opportunistic scheduling was initially proposed to exploit user channel diversity for network capacity enhancement. However, the achievable gain of opportunistic schedulers is generally restrained due to fairness considerations which impose a tradeoff between fairness and throughput. In this paper, we show via analysis and numerical simulations that opportunistic scheduling not only increases network throughput dramatically, but also increases energy efficiency and can be fair to the users when they cooperate, in particular by using D2D communications. We propose to leverage smartphone's dual-radio interface capabilities to form clusters among mobile users. We design simple, scalable and energy-efficient D2D-assisted opportunistic strategies, which would incentivize mobile users to form clusters. We use a coalitional game theory approach to analyze the cluster formation mechanism, and show that proportional fair-based intra-cluster payoff distribution brings significant incentive to all mobile users regardless of their channel quality.

“Destripa” un móvil, un televisor, el cuerpo humano, … con la ayuda de los investigadores de los Institutos IMDEA Descubre la enorme cantidad de ciencia y tecnología que rodea nuestra vida, haciéndola más cómoda, fácil y segura; y conoce a quienes se dedican a que cada día una y otra continúen mejorando. La Ciencia del Salón de tu casa es la actividad con la que los institutos IMDEA participan este año en la iniciativa europea La Noche de los Investigadores. Su principal objetivo es mostrar al público que en casi todos los objetos y servicios que nos rodean hay mucha ciencia y mucha tecnología, y hacerlo dejando que el público interactúe con el investigador y mostrando el atractivo de quienes se dedican a mejorarlos. En definitiva, lo que se persigue es analizar con la ayuda del público lo diferente que sería nuestra vida sin ellos: los objetos o servicios y los investigadores, para resaltar lo importantes que son la ciencia y la tecnología para el bienestar social y lo interesante y gratificante que es dedicarse a ellas.

Handoff is a key element in the wireless cellular networks in order to provide Quality of Service (QoS) to the users and to support users’ mobility. Handoff failure will result in the forced termination of an ongoing call. From the user’s point of view, the service of a handoff request is more important, as the forced termination of an ongoing call is more annoying than the blocking of new calls. Therefore, in order to support QoS to the users and to provide ubiquitous coverage, the handoff procedure should be further investigated. The aim of this lecture is to provide a comprehensive survey of the basic elements, the different types and phases of the handoff procedure.

The EC FP7 Network of Excellence TREND (Towards Real Energy-efficient Network Design – see http://www.fp7-trend.eu/ ) organizes a PhD School in the field of energy-efficient networking, encompassing all issues that relate to a wiser, more parsimonious, approach to energy consumption in networking.

In this paper we explore the problem of achieving efficient packet transmission over unreliable links with worst case occurrence of errors. In such a setup, even an omniscient offline scheduling strategy cannot achieve stability of the packet queue, nor is it able to use up all the available bandwidth. Hence, an important first step is to identify an appropriate metric for measuring the efficiency of scheduling strategies in such a setting. To this end, we propose a relative throughput metric which corresponds to the long term competitive ratio of the algorithm with respect to the optimal. We then explore the impact of the error detection mechanism and feedback delay on our measure. We compare instantaneous error feedback with deferred error feedback that requires a faulty packet to be fully received in order to detect the error. We propose algorithms for worst-case adversarial and stochastic packet arrival models, and formally analyze their performance. The relative throughput achieved by these algorithms is shown to be close to optimal by deriving lower bounds on the relative throughput of the algorithms and almost matching upper bounds for any algorithm in the considered settings. Our collection of results demonstrates the potential of using instantaneous feedback to improve the performance of communication systems in adverse environments.

​We describe the design and implementation of DeepDive, a system for transparently identifying and managing performance interference between virtual machines (VMs) co-located on the same physical machine in Infrastructure-as-a-Service cloud environments. DeepDive successfully addresses several important challenges, including the lack of performance information from applications, and the large overhead of detailed interference analysis. We first show that it is possible to use easily-obtainable, low-level metrics to clearly discern when interference is occurring and what resource is causing it. Next, using realistic workloads, we show that DeepDive quickly learns about interference across co-located VMs. Finally, we show DeepDive’s ability to deal efficiently with interference when it is detected, by using a low-overhead approach to identifying a VM placement that alleviates interference.

In this self-contained talk I will describe few combinatorial results that were initiated by problems from several application areas. These results include the following: (1) the use of the Cycle Lemma in deriving statistics about several classes of trees (this includes, as a start, a very simple proof for the Catalan number of binary trees), (2) a new characterization of tree medians, (3) an algorithm for generation of permutations, (4) a result about the volume of discrete spheres, and (5) a combinatorial problem that resulted in a paper with Paul Erdős

WoWMoM 2013 is the 14th IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks. WoWMoM addresses research challenges and advances towards a world of wireless, mobile, and multimedia pervasive communications.