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.

La Universidad Carlos III de Madrid (UC3M) participa en la decimoséptima edición de la Semana de la Ciencia de Madrid con más de una treintena de actividades gratuitas que permiten conocer de primera mano la I+D+i de la institución. IMDEA Networks colabora en un espectáculo multimedia, teatral y divulgativo para explorar los efectos de la tecnología 5G en la vida cotidiana  que se celebrará el 7 de noviembre en el Auditorio de la UC3M.  

Ander Galisteo, estudiante de doctorado en Ingeniería Telemática en el instituto de investigación IMDEA Networks, ha sido invitado a impartir esta charla de divulgación científica dentro del programa "Jóvenes Científicos 2017" de la Semana de la Ciencia de Madrid. 

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%.

One of the most promising options to significantly increase data rates in future wireless networks is to vastly increase the communication bandwidth. Such very high bandwidth channels are only available in the extremely high frequency part of the radio spectrum, the millimeter wave band (mm-wave).

Tablets and smartphones have become the favorite gateway to the Internet for a majority of users. Being equipped with plenty of sensors, these devices enable far more than traditional web browsing.

El congreso “IFIP Performance” reúne a investigadores interesados en la comprensión y mejora del desempeño de los sistemas de comunicación mediante modelos cuantitativos y técnicas de solución de última generación.

One of the most important achievements of Software-Defined Networking is a possibility to redefine existing invariants in network management, This talk covers three important aspects of data path provision: (1) what should be flexible at the network element level to express various economic models and how different characteristics impact desired objective functions?; (2) how to represent this expressiveness efficiently on data plane; and 3) new abstractions that allow to integrate services from heterogeneous controllers without standardization of Northbound API.

The main functionality of the Internet is to provide global connectivity for every node attached to it. In light of the IPv4 address space depletion, large networks are in the process of deploying IPv6. In this paper we perform an extensive analysis of how BGP route propagation affects global reachability of the active IPv6 address space in the context of this unique transition of the Internet infrastructure. We propose and validate a methodology for testing the reachability of an IPv6 address block active in the routing system. Leveraging the global visibility status of the IPv6 prefixes evaluated with the BGP Visibility Scanner, we then use this methodology to verify if the visibility status of the prefix impacts its reachability at the interdomain level. We perform active measurements using the RIPE Atlas platform. We test destinations with different BGP visibility degrees (i.e., limited visibility - LV, high visibility - HV and dark prefixes). We show that the IPv6 LV prefixes (v6LVPs) are generally reachable, mostly due to a less-specific HV covering prefix (v6HVP). However, this is not the case of the dark address space, which, by not having a covering v6HVP is largely unreachable. When talking about the results we present in this paper a better explanation of trace route and some basic concepts of BGP will be provided.

In this talk, we discuss a theoretical framework to evaluate the throughput of underwater networks over an ensemble of node topologies and propagation environments. We start with a review of the properties of underwater acoustic communications.