Visible Light Communication (VLC) is an emerging technology in which Light Emitting Diodes (LEDs) transport information wirelessly, using the visible light spectrum. While most of the research on VLC has focused on wideband white LEDs used in ambient illumination, narrowband and colored LEDs have received little attention. Short-range free-space optical communication based on narrowband LEDs as visible light transmitters and receivers enable a variety of applications, a scenario we refer as LED-to-LED communication. In this work, we introduce the communication and networking protocols of LED-to-LED communication. Our work addresses fundamental challenges such as efficient collision detection medium access protocol and elimination of light flicker. We build a prototype and demonstrate bi-directional data exchange in a network of up to four LEDs. We further study the trade-offs in the system design and measure the achievable bit-rate and transmission distances

On Jan 8-9, 2013, the kick-off meeting of Research & Development project CROWD (Connectivity management for eneRgy Optimised Wireless Dense networks) was held in Pisa (Italy). CROWD is co-funded by the European Commission within the Seventh Framework Programme (FP7).

Wireless sensor network and wireless multimedia network technologies combined with interactive 3D virtual visualization can converge into really interesting and functional applications such as detailed real-time monitoring of environments, emergency response and preparedness, distributed collaborative training, and remote walkthroughs, just to name a few examples. With the recent advances in wireless communication, and the proliferation of portable computer and micro-sensor devices, we are witnessing a growing interest in using wireless multimedia sensor networks and collaborative virtual environment technologies for safety and security class of applications.

Internal BGP (iBGP) is used to distribute interdomain routes within a single ISP. The interaction between iBGP and the underlying IGP can lead to routing and forwarding anomalies. For this reason, several research contributions aimed at defining sufficient conditions to guarantee anomaly-free configurations and providing design guidelines for network operators.

We design an adaptive modulation scheme to support opportunistic multicast scheduling in wireless networks. Whereas prior work optimizes capacity, we investigate the finite horizon problem where (once or repeatedly) a fixed number of packets has to be transmitted to a set of wireless receivers in the shortest amount of time — a common problem, e.g., for software updates or video multicast.

It is common practice for network operators, usually for traffic engineering purposes, to propagate more specific prefixes (overlapping prefixes) along with shorter prefixes that cover them. On the other hand, it can be beneficial for some Autonomous Systems (ASes) to filter such overlapping prefixes

This seminar builds on your basic knowledge of computer networks from an introductory computer networks class or equivalent. It covers mathematical and algorithmic foundations of the essential networking functions of data transfer, transfer control, and management. Essential concepts of some techniques, such as optimization, control theory, queuing theory, and their application to networks are covered.

In this talk, I will present SOFT, a tool for testing the interoperability of OpenFlow switches. Our key insight is in automatically identifying the testing inputs that cause different OpenFlow agent implementations to behave inconsistently. To this end, we first symbolically execute each agent under test in isolation to derive which set of inputs causes which behavior. We then crosscheck all distinct behaviors across different agent implementations and evaluate whether a common input subset causes inconsistent behaviors. Our evaluation shows that our tool identified several inconsistencies between the publicly available Reference OpenFlow switch and Open vSwitch implementations.

This is the kick-off meeting of the iJOIN EU FP7 project. It will consist of a series of presentations of work packages 2-4 intended to shape the first steps of the project. WP2-4 will be presented during 90 minute slots by each Work Package leader.

El próximo miércoles, 13 de noviembre, se celebra en la Escuela Politécnica Superior (Campus de Leganés) de la Universidad Carlos III de Madrid (UC3M), la próxima reunión de ESNOG/GORE (España Network Operators Group / Grupo de Operadores de Red Españoles), contando con el patrocinio de la Cátedra Telefónica de la UC3M y ESPANIX (Punto neutro Español de Internet). Es una jornada que tendrá en agenda una serie de conferencias y mesas redondas sobre Internet a nivel de red.