Comments and feedback to Dario Rossi
Past seminars
Friday July 24th,14h-16h (Amphi Rubis)
Pr. Erol Gelenbe,Imperial College London
Steps toward self-aware networks
Web:http://www.ee.ic.ac.uk/gelenbe/
Abstract:This talk focuses on how network software adapts to user needs,load variations and failures to provide reliable communications in largely unknown networks. For more details,see Steps toward self-aware networks ,in Communications of the ACM,Volume 52,Issue 7,July 2009
Bio: Erol Gelenbe (FACM,FIEEE,FIEE) has been characterized as the single individual who,over a span of 30 years,has made the greatest overall contribution to the field of Computer System and Network Performance Evaluation through research,doctoral training,wide ranging international collaboration,and professional service. He holds the “Dennis Gabor Chair” at Imperial College,and his papers in 2007-2008 appear in the ACM Trans. on Sensor Networks,ACM Transactions on Internet Technology,Neural Computation,Performance Evaluation,Physical Review,Proceedings of the Royal Society A,and The Computer Journal. He has made decisive contributions to product form networks by inventing G-networks (Gelenbe-Networks) with totally new types of “negative customers,triggers,and resets”,and which are characterised by non-linear traffic equations. He has made seminal contributions to random access communications,the optimisation of reliability in database systems,the design of adaptive QoS-aware packet networks,diffusion models in performance analysis,and the performance of link control protocols.
A native of Turkey who graduated from the Middle East Technical University in Ankara,he has authored four books written in English and French,two of which have appeared in Japanese and Korean translation,and over 115 journal articles in the Journal of the ACM,Physical Review,Acta Informatica,Proceedings of the Royal Society,Management Science,IEEE Trans. on Computers,IEEE Trans. on Neural Networks,IEEE Trans. on Software Engineering,IEEE Trans. on Systems Man and Cybernetics,IEEE J. on Selected Areas in Communications,ACM Trans. on Sensor Networks,Communications of the ACM,Journal of Applied Probability,and Theoretical Computer Science,etc.. His recent work includes path finding algorithms in noisy and uncertain conditions,networked auctions,the use of neural networks to control routing in computer networks,as well as theoretical biology and theoretical chemistry including the analysis of neural networks and gene regulatory networks. His research is currently funded by industry (GD,BAE Systems and QinetiQ),and by agencies including EPSRC,MoD and DoD,and the EU.
A founder of IFIP WG7.3 and of ACM SIGMETRICS,and of the journal Performance Evaluation,Erol is particularly proud of the 58 PhD students he has graduated,many of whom are prominent in academia and industry in France,the USA,Turkey,Greece,UK,Canada,Belgium and Venezuela. Appointed to a chair at the age of 27 at the University of Liège in Belgium,he founded performance modelling at INRIA and in French Universities. His professorial posts include the University of Paris-Orsay,the University of Paris-Descartes,New Jersey Institute of Technology,Duke University and the University of Central Florida. He is now Editor-in-Chief of The Computer Journal (British Computer Society),and serves on the editorial board of several journals. Erol is currently a member of the Science and Technology Board and of the Executive Board of the UK Defence Technology Centre on Data and Information Fusion. His experience includes being Department Head at Duke University (USA),Associate Dean at the University of Central Florida (USA),and chairing the Technical Advisory Board of the US Army’s Simulation and Training Command (1999-2003).
His honours include:Commander of Merit of the Republic of Italy,Grand Officer of the Star of Italy,Officer Order of Merit of France and Chevalier des Palmes Académiques. Member of the French National Academy of Engineering,Turkish Academy of Sciences,Academia Europaea. He received the Science Award (1994) of the Parlar Foundation in Turkey,was the first computer scientist to be awarded the Grand Prix France Telecom (1996) of the French Academy of Sciences,and received “honoris causa” doctorates from the University of Rome II (1996),Bogaziçi University,Istanbul (2004),and the University of Liège,Belgium.
Thursday May 28th,14h-15h (Amphi Saphir)
Minh Anh Tran,PostDoc at ENST
Théorie des jeux pour la modélisation des terminaux mobiles multi-homés
Web:http://tranminhanh.free.fr/
Short Bio:Minh Anh Tran est sorti de l’école polytechnique en 2004. Il a fait ensuite une thèse en Informatique et Réseaux dans l’équipe TREC à l’ENS d’Ulm. L’année dernière,il a fait un postdoc à Stanford,et maintenant,il travaille avec Nadia Boukhatem dans le projet 3MING.
Abstract:Chaque terminal est équipé aujourd’hui de plusieurs interfaces de technologies radio différentes. Il devient possible d’utiliser simultanément les différentes interfaces,et non seulement de basculer d’un réseau à un autre. Les terminaux sont en concurrence entre eux pour l’accès aux ressources de différents réseaux,chacun cherchant à satisfaire un optimal local (stratégie dite égoïste). Cela relève un problème d’optimisation multi-objectif qui peut être étudié en utilisant la théorie des jeux. Dans notre modèle,les terminaux tournent plusieurs applications en même temps et peuvent associer chaque application à une interface spécifique afin de maximiser leur fonction d’utilité. Nous montrons qu’avec un mécanisme de prix approprié,le système tend vers des équilibres qui réalisent un optimal global. Enfin,nous présentons quelques perspectives de ce travail.
Thursday April 16th,14h-16h (Amphi Grenat)
Guillaume Valadon,PhD
Mesure et analyse des reseaux
Web:http://valadon.complexnetworks.fr/
Abstract:Guillaume Valadon est post-doctorant au sein de l’équipe Complex Networks ( http://complexnetworks.fr/ ) au LIP6. Durant sa thèse,effectuée entre le Japon et la France,il a travaillé sur la mobilité au sens large;notamment MANET,Mobile IPv6,ainsi que la sécurité de ces protocoles (voir http://valadon.complexnetworks.fr/ ).
Lors de cette présentation,il abordera deux améliorations de Mobile IPv6,l’une pratique l’autre théorique. Ces deux approches complémentaires compatibles avec l’infrastructure actuelle de l’Internet,permettent de gérer la mobilité de façon transparente à la fois pour le réseau et les périphériques fixes.
Dans une seconde partie,il discutera de travaux en cours portant sur la dynamique de la topologie d’Internet,et l’analyse du trafic d’un serveur eDonkey. Plus particulièrement,il sera abordé la mesure de la topologie de l’Internet depuis une source vers un ensemble de destinations ainsi que l’évolution de cette topologie au cours du temps. En ce qui concerne eDonkey,des résultats préliminaires visant à identifier les échanges de fichiers pédophiles seront discutés.
Thursday February 12th,14h-16h (Amphi Saphir)
Pr. Marceau Coupechoux,ENST
Analytical Evaluation of Various Frequency Reuse Schemes in OFDMA Networks
Web:http://www.enst.fr/~coupecho
Abstract:In this presentation,we present an analytical solution to carry out performance analysis of various frequency reuse schemes in an OFDMA based cellular network (like WiMAX or LTE networks). We study the performance in downlink in terms of signal to interference (SIR) ratio and cellular capacity. Analytical models are proposed for integer frequency reuse (IFR),fractional frequency reuse (FFR) and two level power control (TLPC) schemes. These models are based on a fluid model originally proposed for CDMA networks. The modeling key of this approach is to consider the discrete base stations entities as a continuum. To validate our approach,Monte Carlo simulations are carried out. Results of validation study show that results obtained through our analytical method are in conformity with those obtained through simulations. However,compared to time consuming simulations,our model is very time efficient. We also present a comparison between above three frequency reuse schemes.
Thursday January 29th,14h-16h (Amphi B312)
Pr. Pascal Urien,TELECOM ParisTech,founder of EtherTrust
Des cartes à puce pour l’Internet,«Are you serious ? ». Petite histoire d’EtherTrust,spin-off de Télécom ParisTech.
Web:http://www.enst.fr/~urien
http://www.ethertrust.com/
Abstract:Internet révolutionne chaque jour un peu plus l’informatique distribuée et les applications multimédia. La toile est un acteur fondamental de l’économie mondiale,dans un environnent émergent ou les technologies des réseaux radio de quatrième génération (4G,WiMAX) amplifient le paradigme du always on. Dans ce contexte la sécurité est souvent citée comme un pré-requis et un enjeu (financier) majeur. Cependant la réalité semble tout autre:bien que la cryptographie ait produite des algorithmes solides et que des preuves formelles existent sur des protocoles tels que SSL,l’internaute utilisent de (trop) nombreux mots de passe et surfe à l’aide d’ordinateurs démunis de sécurité physique. Par ailleurs une société connectée en permanence,amplifie l’effet big brother,c’est-à-dire la contradiction entre le respect de la vie privée (privacy) et la traçabilité induite par les technologies radio enfouies. Dans cet exposé nous présenterons quelques résultats significatifs ainsi que le modèle de sécurité que nous avons bâti,reposant sur une pile à trois niveaux:sécurité des accès,des VPN,et des applications. L’originalité de cette approche est de s’appuyer sur une architecture collaborative entre des terminaux ou des serveurs informatiques muni de grande puissance de traitement mais non sécurisés,et des modules de sécurité (des cartes à puce) garantissant une sécurité forte mais offrant de faibles capacités de calcul. C’est une recherche pragmatique,nous collaborons étroitement avec l’industrie mais également avec les organismes de normalisation tels que l’IETF. EtherTrust,est une spin-off (fondée en 2007) issue de ces travaux,qui a pour objectif de commercialiser des solutions,des matériels et des logiciels dédiés à la sécurité d’un monde convergent tout IP. Sa principale originalité est de s’appuyer sur une technologie carte à puce,dont les principaux acteurs industriels sont Européens et plus particulièrement Français.
Monday December 8th,14h-15h (Amphi Jade)
Pr. Dario Rossi,TELECOM ParisTech
Stochastic Packet Inspection for Automated Traffic Classification
Web:http://www.enst.fr/~drossi
Abstract:This talk focuses on KISS,a new addition to the well populated and flavored world of Internet classification engines. Motivated by the expected raise of UDP traffic volume,which stems from the momentum of P2P streaming applications,we propose a novel statistical payload-based classification framework,targeted to UDP traffic. Statistical signatures are automatically inferred from training data,by the means of a Chi-Square like test,which extracts the protocol “syntax”,but ignores the protocol semantic and synchronization rules. The signatures feed a decision engine based on Support Vector Machines. KISS is very efficient,and its signatures are intrinsically robust to packet sampling,reordering,and flow asymmetry,so that is can be used on almost any network. KISS is tested in different scenarios,considering both data,VoIP,and traditional P2P Internet applications. Results are astonishing. The average True Positive percentage exceeds 99%,and than 0.05% of False positives are raised. But KISS is also proved to provide almost perfect results when facing new P2P streaming applications,such as Joost,PPLive,SopCast and TVants. Finally,we present how KISS can be extented to the TCP case and present preliminary results.
Monday,November 3rd,14h30 –15h30 (Amphi Saphir)
Pr. Jean-Pierre HUBAUX,Ecole Polytechnique de Lausanne (EPFL)
Game Theory and Wireless Security
Web:http://people.epfl.ch/jean-pierre.hubaux
Abstract:Securing wireless networks is notoriously a huge challenge. In this talk,we will first describe current trends in wireless technology and upcoming wireless networks,such as sensor,vehicular,mesh,and RFID networks. We will then address their vulnerabilities and the existing or envisioned protection techniques. We will then consider the specific example of ephemeral networks,namely networks in which the interactions between nodes are short-lived,typically due to their mobility. We will focus on the fundamental security operation of revocation in such networks. We will show how game theory can be used to model the different possible revocation strategies of the nodes and discuss the implications of this model on the protocol design.
Monday,November 3rd,16h00 –17h00 (Amphi Saphir)
Pr. Tamer BASAR,University of Illinois at Urbana-Champaign
Optimum Active Pricing for Communication Networks
Web:http://decision.csl.uiuc.edu/~tbasar/
Abstract: The talk will introduce a class of hierarchical games that arises in pricing of services in communication networks with a monopolistic service provider and a large population of users of different types. The probability distribution on different user types is common/public information,but the precise type of a specific user is not necessarily known to all parties. As such the game falls in the class of games with incomplete information,and in our specific case what we have is a problem of mechanism design within an uncertain environment and with asymmetric information. The service provider is a revenue maximizer,with his instrument being the prices charged (for bandwidth) as a function of the information available to him. The individual users are utility maximizers,with bandwidth usage being their decision variable. The congestion cost in their utility functions creates a coupling between different users’objective functions,which leads to a non-cooperative game at the lower (users) level for which we adopt Nash or Bayesian equilibrium. Solutions to these problems (at both the lower and the upper levels) entail non-standard multi-level optimization problems. Indirect approaches to these optimization problems will be presented,and some asymptotics for large agent-population models will be discussed. (This is based on joint work with Hongxia Shen.)
