Programa:

09:00 - 09:30 Bienvenida y registro de asistentes

09:30 - 09:50 Apertura de la jornada
D. Arturo Azcorra, Director General, CDTI
D. Francisco Marín, Presidente Área de Actuación de Innovación Tecnológica, AETIC
D. Albert Banchs, Director, Institute IMDEA Networks
D. Carlos Balaguer, Vicerrector de Investigación, UC3M

09:50 - 10:15 Presentaciones
Presentación del Institute IMDEA Networks, D. Albert Banchs (  Descargar presentación 2006 Kb )
Presentación del departamento de I+D+i de AETIC, D. Juan Gascón, Director de Contenidos Digitales e I+D+i de AETIC
(  Descargar presentación 2256 Kb )

10:15 - 11:00 Bloque “Eficiencia Energética”
Energy-efficient Networking at Institute IMDEA Networks
D. Antonio Fernández Anta, Senior Researcher, Institute IMDEA Networks (  Descargar presentación 160 Kb )
TELVENT Energía
D. Francisco Romero, Director Desarrollo de Negocio (  Descargar presentación 1.757 Kb )
INDRA
Dña. Marta Arias, Gerente Área de Eficiencia Energética (  Descargar presentación 538 Kb )

The talk consists of two parts. The first part will present an overview on the current research activities of iNEXT (Centre for Innovation in IT applications and Services) at the University of Technology, Sydney. This includes a brief description of our Sensor Grid for Assistive Healthcare project.

Improving the energy-efficiency of core routers is important for ISPs and equipment vendors alike. We tackle this problem by focusing on packet buffers in backbone router line-cards. We broadly classify the talk into two parts - an evolutionary approach and a clean-slate design. In the former, we propose a simple power saving mechanism that turns buffers on/off to save energy. Our scheme can be incrementally deployed today and requires minimal changes to existing line-card design. In the latter, we examine the impact of very small buffers when both real-time and TCP traffic coexist in the network.

BitTorrent is the most popular P2P content delivery appli-cation where individual users share various type of content with tens of thousands of other users. The growing popular-ity of BitTorrent is primarily due to the availability of valuable content without any cost for the consumers. However, apart from required resources, publishing (sharing) valuable (and often copyrighted) content has serious legal implica-tions for users who publish the material (or publishers). This raises a question that whether (at least major) content publishers behave in an altruistic fashion or have other incentives such as financial. In this study, we identify the content publishers of more than 55K torrents in two major BitTorrent portals and examine their behavior. We demonstrate that a small fraction of publishers is responsible for 67% of the published content and 75% of the downloads. Our investigations reveal that these major publishers respond to two dif-ferent profiles. On the one hand, antipiracy agencies and ma-licious publishers publish a large amount of fake files to protect copyrighted content and spread malware respectively. On the other hand, content publishing in BitTorrent is largely driven by companies with financial incentives. Therefore, if these companies lose their interest or are unable to publish content, BitTorrent traffic/portals may disappear or at least their associated traffic will be significantly reduced.

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Lugar: 
Fecha: 19 de octubre, 2010, 16:00h
Organización: 

Since its inception in 2005, YouTube has seen explosive growth in its popularity; today it is indisputably the world’s largest video sharing site. Given the number of viewers and the accompanying traffic volume, its geographical span and scale of operations, the design of YouTube’s content delivery infrastructure is a highly challenging engineering task. In this talk, I will present our recent studies on "reverse-engineering" the YouTube video delivery system through passive and active measurements.

This talk will introduce P2PSIP (Peer-to-peer Session Initiation Protocol) technologies, including the most common protocols and algorithms. The talk will also discuss the performance of these technologies in different network settings and the tradeoffs associated with deploying P2PSIP systems. Additionally, the talk will cover issues related to security and NAT traversal.

Content-Centric Networking (CCN) is a clean-slate proposal to replace/enrich the current Internet. CCN is focused on content instead of machines, so users can request a given content by sending Interest messages with the name of the content. CCN routers have three main data structures: a FIB mapping content names to outbound faces, a Content Store to cache data packets and a pending Interest table (PIT) to forward incoming packets towards the consumers, using a breadcrumb mechanism. Security is part of the proposal, as all data packets are signed by its publisher.

802.11 wireless local area networks have been designed for wireless communication. The principle for 802.11 communication is that frames are acknowledged (ACKed) after a short and predefined MAC idle time. Despite the MAC idle time is designed to be constant, we find that it varies with i) the physical distance between stations, caused by the delay of wireless signal propagation, and ii) the time to detect the ACK at the local station, which varies with the signal strength of the incoming ACK. Exploiting this knowledge, we present CAESAR, CArriEr Sense-bAsed Ranging, that combines time-of-flight and signal-to-noise ratio measurements to calculate the distance between two stations. CAESAR measures the distance by estimating the MAC idle time in a data/ACK communication at a 44 MHz clock resolution and the ACK detection time on a per-frame basis. CAESAR is a software-based solution that is entirely implemented at the transmitter and it requires no 802.11 protocol modifications. We implement CAESAR on commodity hardware and conduct extensive experiments both in controlled network conditions and dynamic radio environments.  Our measurements confirm the accuracy of the solution and show the capability to track the distance to WLAN smartphones at pedestrian speeds.

The work above has been conducted at Disney Research and published at ACM Conext'11.

The last part of the talk will briefly present ongoing research activities conducted at ETHZ in the area of time-of-flight WLAN localization.

​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.