WEBLab


  

Past events

  • Giovedì, 1 luglio 2010 -- Ore 11
    Dipartimento di Ingegneria dell'Informazione, Sala riunioni primo piano
    On the Internet someone knows you are a dog
    Balachander Krishnamurthy
    AT&T Research, New Jersey

    Abstract: For the last few years we have been examining the leakage of privacy on the Internet: how information related to individual users is aggregated as they browse seemingly unrelated Web sites. Thousands of Web sites across numerous categories, countries, and languages were studied to generate a privacy "footprint". I will report on our longitudinal study consisting of multiple snapshots of our examination of such diffusion over six years. We examine the various technical ways by which third-party aggregators acquire data and the depth of user-related information acquired. We explore limitations of techniques for protecting privacy diffusion. Our results show increasing aggregation of user-related data by a steadily decreasing number of entities. I will also talk about a recent discovery of large-scale leakage of personally identifiable information (PII) via Online Social Networks (OSN). Third-parties can link PII with user actions both within OSN sites and elsewhere on non-OSN sites. Time permitting I will also cover leakage in mobile online social networks.

    Author: Balachander Krishnamurthy has been with AT&T Labs--Research since his PhD. His main focus of research of late is in the areas of Internet privacy, Online Social Networks, and Internet measurements. He has authored and edited ten books, published over 80 technical papers, holds twenty patents, and has given invited talks in over thirty countries. He co-founded the successful Internet Measurement Conference and Steps to Reducing Unwanted Traffic on the Internet workshop. In 2008 he co-founded the ACM SIGCOMM Workshop on Online Social Networks. He has been on the thesis committee of several PhD students, collaborated with over seventy researchers worldwide, and given tutorials at several industrial sites and conferences. His most recent book "Internet Measurements: Infrastructure, Traffic and Applications" (525pp, John Wiley & Sons, with Mark Crovella), was published in July 2006 and is the first book focusing on Internet Measurement. His previous book 'Web Protocols and Practice: HTTP/1.1, Networking Protocols, Caching, and Traffic Measurement' (672 pp, Addison-Wesley, with Jennifer Rexford) is the first in-depth book on the technology underlying the World Wide Web, and has been translated into Portuguese, Japanese, Russian, and Chinese.

  • Lunedì, 2 novembre 2009 -- Ore 17
    SIMCAN: A very flexible and scalable simulation framework for Computer Architectures and Networks
    Alberto Nunez Covarrubias
    University Carlos III of Madrid

    Abstract: In this talk will be presented SIMCAN, a tool to perform analysis of Parallel and Distributed environments, which manage a great amount of I/O operations, on large storage networks. Thus, we will able to study the behaviour of complex distributed environments to several purposes, like detecting system bottlenecks, calculating the scalability degree of the system or testing the performance of developed algorithms, without using a real system. Storage subsystem performance is one of the major concerns that arise on large storage networks. Major requirements for storage networks are scalability and performance. In those kinds of networks, defining an architecture that satisfies those requirements is a very difficult task. With SIMCAN, custom environments can be configured and deployed on a flexible and easy way. In fact, the most interesting features of this simulation tool are its flexibility and scalability, so the simulation of distributed storage environments can be performed with the required detail level. Thus, in order to evaluate the benefits and the accuracy of the proposed tool, we have tested it with a typical high performance application, and compared the results of the simulated architecture with the real one.

  • Martedì, 3 novembre 2009 -- Ore 17
    HIDDRA: Highly Independent Data Distribution and Retrieval Architecture
    Alberto Nunez Covarrubias
    University Carlos III of Madrid

    Abstract: Institutions such as NASA, ESA or JAXA find solutions to distribute data from their missions to the scientific community, and their long term archives. This is a complex problem, as it includes a vast amount of data, several geographically distributed archives, heterogeneous architectures with heterogeneous networks, and users spread around the world. We propose a novel architecture that solves this problem aiming to fulfill the requirements of the final user. Our architecture is a modular system that provides a highly efficient parallel multiprotocol download engine, using a publisher/subscriber policy which helps the final user to obtain data of interest transparently.

  • Venerdì, 24 ottobre 2008 -- Ore 15
    Dipartimento di Ingegneria dell'Informazione, Sala riunioni primo piano
    Active Management of Energy in IT systems
    Ing. Danilo Ardagna
    Politecnico di Milano.

    Abstract: In recent years, the energy consumption associated with Information Technology (IT) infrastructures has been steadily increasing. The reduction of energy usage is one of the primary goals of green computing, a new discipline and practice of using computing resources with a focus on the impact of IT on the environment. For example, the US Department of Energy’s 2007 estimate of 59 billion kWh spent in US data centres translates to several million tons of coal consumption and CO2 emission per year. Overall, IT accounts for 2% of global CO2 emissions, i.e., IT pollutes to the same extent as the global air traffic. A significant amount of work has been done to achieve power reduction of hardware devices (e.g., in mobile systems to extend battery life). Nowadays, low power techniques and energy savings mechanisms are being introduced also in data centers environments. In such systems, software is accessed as a service and computational capacity is provided on demand to many customers who share a pool of IT resources. Energy savings can be obtained by dynamically allocating computing resources among running applications and trading off application performance levels with energy consumption. As the customers’ access rates change significantly within a single business day, energy-aware resource allocation is a challenging problem and techniques able to control the system at very fine grained time scales and in transient conditions are needed. The aim of the seminar is to introduce novel resource allocation policies for energy-aware computing systems grounded on expertise from several research areas: service technologies, optimization, performance evaluation, model identification and control theory.

  • Mercoledì, 23 maggio 2006 -- Ore 14:30
    Aula FA-1B della Facoltà di Ingegneria di Modena. BAR Gossip
    Prof. Lorenzo Alvisi
    Department of Computer Sciences at the University of Texas at Austin.

    Abstract: The promise of robustness and scalability in peer-to-peer systems can quickly evaporate without mechanisms to encourage faithful participation of the peers to the protocol and techniques to handle arbitrary behavior among peers. This talk will present FlightPath, the first peer-to-peer streaming application that guarantees predictable throughput and low- latency in the Byzantine-Altruistic-Rational (BAR) model, in which peers not following the protocol can behave in a self-serving (rational) or arbitrary (Byzantine) way.

    At the core of our solution is a BARtolerant version of gossip, a well-known technique for scalable and reliable data dissemination. BAR Gossip relies on verifiable pseudo-random partner selection to eliminate non-determinism that can be used to game the system while maintaining the robustness and rapid convergence of traditional gossip. A novel fair enough exchange primitive entices cooperation among selfish nodes on short timescales, avoiding the need for long-term node reputations. Our initial experience provides evidence for BAR Gossip's robustness. Our BAR-tolerant streaming application provides over 99% convergence for broadcast updates when all clients are selfish but not colluding, and over 95% convergence when up to 40% of clients collude while the rest follow the protocol. BAR Gossip also performs well when the client population consists of both selfish and Byzantine nodes, achieving over 93% convergence even when 20% of the nodes are Byzantine.

  • Giovedì, 7 luglio 2005 -- Ore 17:00
    Sala del Consiglio -- Dipartimento di Ingegneria dell'Informazione
    Università di Modena e Reggio Emilia
    Via Vignolese 905, Modena
    SECURE AUTHENTICATION WITHOUT (TRADITIONAL) CRYPTOGRAPHIC KEYS
    Prof. Jonathan Katz
    Department of Computer science
    University of Maryland

    Abstract: Methods for achieving secure authentication between parties holding traditional cryptographic keys are, by now, well understood. For the case of authenticating human users, however, cryptographic keys are not always available: humans simply cannot memorize long, high-entropy keys, and "tokens" (or smartcards) for storing such keys are not yet in widespread use.

    In this talk, I will survey recent research aimed at enabling secure authentication without traditional cryptographic keys, focusing on the use of (1) short, low-entropy passwords or (2) biometric data such as fingerprints or retinal scans.

  • Lunedì, 7 febbraio 2005 -- Ore 15
    Aula FA-1B -- Facoltà di Ingegneria
    Università di Modena e Reggio Emilia
    Via Vignolese 905, Modena
    MOHONK: MOBILE HONEYPOTS TO TRACE UNWANTED TRAFFIC EARLY
    Dr. Balachander Krishnamurthy
    AT&T Labs -- Research

    Abstract: Honeypots have been traditionally used to advertise dark address space and gather information about originators of traffic to such addresses. With simple thresholding mechanisms this technique has shown itself to be fairly effective in identifying suspicious IP addresses. Honeypots are however unsuitable to locate the precise entry point of unwanted traffic. Tracing back to the origination of such traffic is hard due to the delay and difficulty of maintaining state along the path of such traffic. We propose a novel mobile honeypot mechanism that allows unwanted traffic to be detected significantly closer to the origin. The mobility in our scheme stems from additional information that is made available to the upstream Autonomous Systems as well as the changes in the set of dark address space advertised. Sharing information with a network of friendly Autonomous Systems has the potential to identify and significantly lower unwanted traffic on such links.

  • Lunedì, 21 febbraio 2005 -- ore 15.30
    Aula FA-1C -- Facoltà di Ingegneria
    Università di Modena e Reggio Emilia
    Via Vignolese 905, Modena
    LA PROGRAMMAZIONE EURISTICA IN LINUX 2.6
    Prof. D.P. Bovet
    Università di Roma "Tor Vergata"

    Abstract: Gli attuali kernel per sistemi operativi multitasking fanno ampio uso di programmi di tipo euristico. Tali programmi risultano particolarmente critici in quanto le prestazioni dell'intero sistema operativo dipendono dalla loro efficacia. In questo seminario, si accennera' in modo sintetico a tre diversi tipi di programmi euristici usati da Linux 2.6 attinenti allo scheduling delle CPU, al read-ahead di file ed al recupero di pagine di memoria. Si evidenziera' inoltre l'importanza di una metodogia di valutazione di programmi euristici per il kernel basata sull'uso di benchmark opportunamente selezionati.

  • Mercoledì, 20 ottobre 2004
    Ore 15:00
    Sala del Consiglio - Dipartimento Ingegneria dell'Informazione
    Università di Modena e Reggio Emilia
    Via Vignolese 905, Modena

    TUTORIAL: Proportional Share: General Model and practical implementations Slide
    SEMINARIO: Exact GPS simulation and its application to an optimally fair scheduler Slide
    Ing. Paolo Valente
    Scuola Superiore Sant'Anna
    Dipartimento di Ingegneria dell'Informazione, Università di Pisa

  • Giovedì, 21 ottobre 2004
    Ore 15:00
    Aula FA-0A - Facoltà di Ingegneria Università di Modena e Reggio Emilia
    Via Vignolese 905, Modena
    Characterizing a Spam Traffic
    Prof. Jussara Marques de Almeida
    Federal University of Minas Garais
    Brazil

Riccardo Lancellotti