Author: Frédéric Le Mouël

CITI Talk: “​​Who will drive cars ? Public Vehicles for Future Urban Transportation”, by Min-You Wu, on 8th November

The next CITI talk will take place on 8th November at 10.30 am in Amphi Chappe.

This talk entitled “Who will drive cars ? Public Vehicles for Future Urban Transportation” will be presented by Min-You Wu, from Shangai Jiao-Tong, China.

Abstract

Urban transportation is undergoing a dramatic change. Conventional transportation consisting of private vehicles, taxis and buses will be substituted by trip service with autonomous vehicles. Transition from owning private vehicles to purchasing trip service is one of the most revolutionary changes in this century.
In this talk we discuss issues of autonomous trip services. We will discuss cost reduction of trip services. Three most important factors for low-cost trip services are manpower, energy and ridesharing. We focus on the ridesharing problem. We will discuss various techniques to increasing the sharing factor including passenger transfer, incentive mechanism and advanced booking.
We propose a new paradigm of transportation system for future smart cities, namely, Public Vehicles (PVs). With PVs, the number of vehicles as well as the required parking space will be significantly reduced. There will be less traffic congestion, less energy consumption and less pollution. The key issue of implementing an effective PV system is to design efficient planning and scheduling algorithms. We compare the PV system with conventional systems.

Speaker biography

Min-You Wu is a Professor in the Department of Computer Science and Engineering at Shanghai Jiao Tong University. He serves as the Chief Scientist at Grid Center of Shanghai Jiao Tong University. He is a research professor of the University of New Mexico, USA. His research interests include wireless and sensor networks, vehicular networks, multimedia networking, parallel and distributed systems, and compilers for parallel computers. He has published over 200 journal and conference papers in the above areas. His research has been supported by National Science Foundation, DoD, DoE, DARPA, China 863 program, China 973 program, Ministry of Education of China and Natural Science Foundation of China. He is a Vice Chair of Technical Committee of Computer Architecture, CCF. He is a senior member of IEEE and CCF.


CITI Talk: “​​Research presentation”, by Mohammad Rmayti, on 21st October

Mohammad RMAYTI, nouvel ATER IF/CITI, va présenter ses travaux de recherche dans le cadre d’un séminaire d’équipe DYNAMID, vendredi 21 octobre à 10h dans le pot de yaourt.

Résumé

Avec l’évolution des besoins d’utilisateurs, plusieurs technologies de réseaux sans fil ont été développées. Parmi ces technologies, nous trouvons les réseaux mobiles ad hoc (MANETs) qui ont été conçus pour assurer la communication dans le cas où le déploiement d’une infrastructure réseaux est coûteux ou inapproprié. Dans ces réseaux, le routage est une fonction primordiale où chaque entité mobile joue le rôle d’un routeur et participe activement dans le routage. Cependant, les protocoles de routage ad hoc tel qu’ils sont conçus manquent de contrôle de sécurité. Sur un chemin emprunté, un nœud malveillant peut violemment perturber le routage en bloquant le trafic. Dans cette thèse, nous proposons une solution de détection des nœuds malveillants dans un réseau MANET basée sur l’analyse comportementale à travers les filtres Bayésiens et les chaînes de Markov. L’idée de notre solution consiste à évaluer le comportement d’un nœud en fonction de ses échanges avec ses voisins d’une manière complètement décentralisée. Par ailleurs, un modèle stochastique est utilisé afin de prédire la nature de comportement d’un nœud et vérifier sa fiabilité avant d’emprunter un chemin. Notre solution a été validée via de nombreuses simulations sur le simulateur NS-2. Les résultats montrent que la solution proposée permet de détecter avec précision les nœuds malveillants et d’améliorer la qualité de services de réseaux MANETs.

Biographie

Après une Licence en Informatique à la Faculté des Sciences de l’Université Libanaise, j’ai fait mon Master 2 Recherche en Gestion des Risques dans les systèmes d’information à l’Ecole Doctorale de l’Université Libanaise. Intéressé par la sécurité de réseaux informatiques, j’ai effectué mon stage de recherche à l’Utt-Troyes sur la détection d’attaques DoS dans les réseaux VoIP. J’ai commencé ma thèse à l’UTT en codirection avec le Groupe Sécurité de Réseaux à Télécom ParisTech, qui portait sur la détection d’attaques DoS dans les réseaux mobiles ad hoc (MANETs). J’ai soutenu mes travaux de recherche le 30 septembre 2016.


CITI Talk: “​​Structured Interference Management: Fundamentals and Algorithms”, by Xinping Yi, on 19th October

The next CITI talk will take place on 19th October at 10 am in Amphi Chappe.

This talk entitled “Structured Interference Management: Fundamentals and Algorithms” will be presented by Xinping Yi,  research and teaching associate at Technische Universität Berlin.

Abstract

In the future large-scale wireless internet of things, spectrum sharing calls for interference management techniques with low-complexity, low signaling overhead and flexible scalability. A pragmatic strategy is to focus on the underlying interference networks, exploiting the structural property of network topologies and the optimality of the simplest techniques of practical interest. In this talk, we focus on the fundamentals and algorithms of two practical interference management techniques — Treating Interference as Noise (TIN) and Topological Interference Management (TIM). The fundamental structural properties for their information-theoretic optimality in terms of (generalized) Degrees-of-Freedom (DoF) are revealed. The insights are also translated into the principles of algorithm design for spectrum sharing mechanisms in device-to-device communications, and edge caching in Fog-RAN under the TIM setting.

Bio

Xinping Yi has been a postdoctoral research associate in Technical University of Berlin, Berlin, Germany, since November 2014. He joined EURECOM, Sophia Antipolis, France in 2011 and received his Ph.D. degree from Telecom ParisTech, Paris, France, in October 2014. From 2009 to 2011, he was a research engineer at Huawei Technologies, Shenzhen, China. His research interests include information theory, signal processing, and machine learning, as well as their applications in wireless communications, content delivery networks and data analytics. X. Yi was a recipient of the 2014 Chinese Government Award for Outstanding Students Abroad.


CITI Talk: “European projects and strategy” by Marie-Cécile Barras and CITI team members, on 10th October

The next CITI talk will take place on 10th October at 10 am in TD-C. This seminar entitled “European projects and strategy” will be presented by Marie-Cécile Barras, in charge of European projects at Insavalor, and by Florent de Dinechin for Socrate, Frédéric Le Mouel for Dynamid, Hervé Rivano for Urbanet, Mathieu Cunche for Privatics, and Olivier Simonin for Chroma.

Abstract

A special CITI seminar on the European projects/strategy will take on a slightly different format from the usual ones.

On the one hand, Marie-Cécile will present an overview of the current/future European calls, the networking meetings, the support tools set up by INSAVALOR, etc.

On the other hand, each CITI team will present its scientific challenges and European strategy/partners.


PhD Defense: “Cooperative communications with Wireless Body Area Networks for motion capture”, by Arturo Jimenez Guizar, on 27th September

The defense will take place on Tuesday 27th September at 10:00 in the Chappe amphitheatre, Chappe Building, INSA Lyon.

It will be in French with slides in English

Jury

Reviewers

JULIEN-VERGONJANNE Anne, Limoges University
BERDER Olivier, Rennes 1 University

President of the jury

LE RUYET Didier, Conservatoire National des Arts et Métiers

Examiner

UGUEN Bernard, Rennes 1 University

Advisors

GORCE Jean-Marie, INSA de Lyon
GOURSAUD Claire, INSA de Lyon

Abstract

Wireless Body Area Networks (WBAN) refers to the family of “wearable” wireless sensor networks (WSN) used to collect personal data, such as human activity, heart rate, sleep sequences or geographical position.

This thesis aims at proposing cooperative algorithms and cross-layer mechanisms with WBAN to perform large-scale individual motion capture and coordinated group navigation applications.

For this purpose, we exploit the advantages of jointly cooperative and heterogeneous WBAN under full/half-mesh topologies for localization purposes, from on-body links at the body scale, body-to-body links between mobile users of a group and off-body links with respect to the environment and the infrastructure. The wireless transmission relies on an impulse radio Ultra-Wideband (IR-UWB) radio (based on the IEEE 802.15.6 standard), in order to obtain accurate peer-to-peer ranging measurements based on Time of Arrival (ToA) estimates. Thus, we address the problem of positioning and ranging estimation through the design of cross-layer strategies by considering realistic body mobility and channel variations.

Our first contribution consists in the creation of an unprecedented WBAN measurement database obtained with real experimental scenarios for mobility and channel modelling. Then, we introduce a discrete-event (WSNet) and deterministic (PyLayers) co-simulator tool able to exploit our measurement database to help us on the design and validation of cooperative algorithms. Using these tools, we investigate the impact of nodes mobility and channel variations on the ranging estimation. In particular, we study the “three-way ranging” (3-WR) protocol and we observed that the delays of 3-WR packets have an impact on the distances estimated in function of the speed of nodes. Then, we quantify and compare the error with statistical models and we show that the error generated by the channel is bigger than the mobility error.

In a second time, we extend our study for the position estimation. Thus, we analyze different strategies at MAC layer through scheduling and slot allocation algorithms to reduce the impact of mobility. Then, we propose to optimize our positioning algorithm with an extended Kalman filter (EKF), by using our scheduling strategies and the statistical models of mobility and channel errors. Finally, we propose a distributed-cooperative algorithm based on the analysis of long-term and short-term link quality estimators (LQEs) to improve the reliability of positioning. To do so, we evaluate the positioning success rate under three different channel models (empirical, simulated and experimental) along with a conditional algorithm (based on game theory) for virtual anchor choice. We show that our algorithm improve the number of positions estimated for the nodes with the worst localization performance.

 


CITI Talk: “Next Generation of Cellular Wireless Networks: Some Preliminary Results on QoE Consistency and Multiple Cell Selection”, by Catherine Rosenberg, on 12th July.

The next CITI talk will take place on 12th July at 11 am in TD-C.

This talk entitled “Next Generation of Cellular Wireless Networks: Some Preliminary Results on  QoE Consistency and Multiple Cell Selection” will be presented by Catherine Rosenberg, professor at the University of Waterloo.

Abstract

Catherine will present preliminary results in next generation of cellular wireless networks on two topics.

The first topic is on the challenges of offering consistent Quality of Experience (QoE) in an environment where due to mobility, arrival and departures and time varying channels, the system state is highly stochastic.The second topic is on multiple cell selection. We aim at answering two questions: 1) how is performance improved? 2) how can it be implemented?

This work was done in collaboration with Fidan Mehmeti and Ararat Shaverdian.

Bio

Catherine Rosenberg is a Professor in Electrical and Computer Engineering at the University of Waterloo. Since June 2010, she holds the Tier 1 Canada Research Chair in the Future Internet. From 1999 to 2004, Prof. Rosenberg was a Professor in the School of Electrical and Computer Engineering at Purdue University.

Prof. Rosenberg is the President of the Scientific Advisory Board of Orange (formerly France-Telecom).  She was elected an IEEE Fellow for contributions to resource management in wireless and satellite networks on 2011 and a Fellow of the Canadian Academy of Engineering in 2013. Her research interests are mainly in three areas: the Internet, Wireless Networks, and Energy Systems.


PhD Defense: “Data aggregation in Wireless Sensor Networks”, by Jin Cui, on 27th June

The defense will take place on Monday 27th June at 14:30 in the Chappe amphitheatre, Chappe Building, INSA Lyon.

The presentation will be in English.

Jury

Reviewers

MINET Pascale, Inria
DIAS DE AMORIM Marcelo, CNRS

Examinators

BEYLOT André-Luc, ENSEEIHT
ROUSSEAU Franck, ENSIMAG
BOUSSETTA Khaled, Université Paris 13

Advisor

VALOIS Fabrice,INSA Lyon

Abstract

Wireless Sensor Networks (WSNs) have been regarded as an emerging and promising field in both academia and industry. Currently, such networks are deployed due to their unique properties, such as self-organization and ease of deployment. However, there are still some technical challenges needed to be addressed, such as energy and network capacity constraints. Data aggregation, as a fundamental solution, processes information at sensor level as a useful digest, and only transmits the digest to the sink. The energy and capacity consumptions are reduced due to less data packets transmission. As a key category of data aggregation, aggregation function, solving how to aggregate information at sensor level, is investigated in this thesis.

We make four main contributions:

Firstly, we propose two new networking-oriented metrics to evaluate the performance of aggregation function: aggregation ratio and packet size coefficient. Aggregation ratio is used to measure the energy saving by data aggregation, and packet size coefficient allows to evaluate the network capacity change due to data aggregation. Using these metrics, we confirm that data aggregation saves energy and capacity whatever the routing or MAC protocol is used.

Secondly, to reduce the impact of sensitive raw data, we propose a data-independent aggregation method which benefits from similar data evolution and achieves better recovered fidelity.

Thirdly, a property-independent aggregation function is proposed to adapt the dynamic data variations. Comparing to other functions, our proposal can fit the latest raw data better and achieve real adaptability without assumption about the application and the network topology.

Finally, considering a given application, a target accuracy, we classify the forecasting aggregation functions by their performances. The networking-oriented metrics are used to measure the function performance, and a Markov Decision Process is used to compute them. Dataset characterization and classification framework are also presented to guide researcher and engineer to select an appropriate functions under specific requirements.


PhD Defense: “Fluxional compiler : seamless shift from development productivity to performance efficiency, in the case of real-time web applications”, by Étienne Brodu, on 21st June

The defense will take place at 14.00 in Amphi Chappe, and will be in French with slides in English.

Jury

Reviewers

Gaël THOMAS, Telecom Sud Paris

Frédéric LOULERGUE, LIFO

Examiners

Floréal MORANDAT, LaBRI

Frédéric OBLÉ, Atos Worldline

Advisor

Stéphane FRÉNOT, INSA Lyon

Abstract

Most of the now popular web services started as small projects created by few individuals, and grew exponentially. Internet supports this growth because it extends the reach of our communications world wide, while reducing their latency. During its development, an application must grow exponentially, otherwise the risk is to be outpaced by the competition.

In the beginning, it is important to verify quickly that the service can respond to the user needs: Fail fast. Languages like Ruby or Java became popular because they propose a productive approach to iterate quickly on user feedbacks. A web application that correctly responds to user needs can become viral. Eventually, the application needs to be efficient to cope with the traffic increase.

But it is difficult for an application to be at once productive and efficient. When the user base becomes too important, it is often required to switch the development approach from productivity to efficiency. No platform conciliates these two objectives, so it implies to rewrite the application into an efficient execution model, such as a pipeline. It is a risk as it is a huge and uncertain amount of work. To avoid this risk, this thesis proposes to maintain the productive representation of an application with the efficient one.

Javascript is a productive language with a significant community. It is the execution engine the most deployed, as it is present in every browser, and on some servers as well with Node.js. It is now considered as the main language of the web, ousting Ruby or Java. Moreover, the Javascript event-loop is similar to a pipeline. Both execution models process a stream of requests by chaining independent functions. Though, the event-loop supports the needs in development productivity with its global memory, while the pipeline representation allows an efficient execution by allowing parallelization.

This thesis studies the possibility for an equivalence to transform an implementation from one representation to the other. With this equivalence, the development team can follow the two approaches concurrently. It can continuously iterate the development to take advantage of their conflicting objectives.

This thesis presents a compiler that allows to identify the pipeline from a Javascript application, and isolate its stages into fluxions. A fluxion is named after the contraction between function and flux. It executes a function for each datum on a stream. Fluxions are independent, and can be moved from one machine to the other, so as to cope with the increasing traffic. The development team can begin with the  productivity of the event-loop representation. And with the transformation, it can progressively iterate to reach the efficiency of the pipeline representation.

 

Résumé

La plupart des grands services web commencèrent comme de simples projets, et grossirent exponentiellement. Internet supporte cette croissance en étendant les communications et réduisant leur latence. Pendant son développement, une application doit croître exponentiellement, sans quoi elle risque de se faire dépasser par la compétition.
Dès le début, il est important de s’assurer de répondre aux besoins du marché : Fail fast. Des langages comme Ruby ou Java sont devenus populaires en proposant la productivité nécessaire pour itérer rapidement sur les retours utilisateurs. Une application web qui répond correctement aux besoins des utilisateurs peut être adoptée de manière virale. Mais à terme, une application doit être efficace pour traiter cette augmentation de trafic.
Il est difficile pour une application d’être à la fois productive et efficace. Quand l’audience devient trop importante, il est souvent nécessaire de remplacer l’approche productive pour un modèle plus efficace. Aucune plateforme de développement ne permet de concilier ces deux objectifs, il est donc nécessaire de réécrire l’application vers un modèle plus efficace, tel qu’un pipeline. Ce changement représente un risque. Il implique une quantité de travail conséquente et incertaine. Pour éviter ce risque, cette thèse propose de maintenir conjointement les représentations productives et efficaces d’une même application.
Javascript est un langage productif avec une communauté importante. C’est l’environnement d’exécution le plus largement déployé puisqu’il est omniprésent dans les navigateurs, et également sur certains serveurs avec Node.js. Il est maintenant considéré comme le langage principal du web, détrônant Ruby ou Java. De plus, sa boucle évènementielle est similaire à un pipeline. Ces deux modèles d’exécution traitent un flux de requêtes en chaînant des fonctions les unes après les autres. Cependant, la boucle évènementielle permet une approche productive grâce à sa mémoire globale, tandis que le pipeline permet une exécution efficace du fait de sa parallélisation.
Cette thèse étudie la possibilité pour une équivalence de transformer une implémentation d’une représentation vers l’autre. Avec cette équivalence, l’équipe de développement peut suivre les deux approches simultanément. Elle peut itérer continuellement pour prendre en compte les avantages des deux approches.
Cette thèse présente un compilateur qui permet d’identifier un pipeline dans une application Javascript, et d’isoler chaque étape dans une fluxion. Une fluxion est nommée par contraction entre fonction et flux. Elle exécute une fonction pour chaque datum sur le flux. Les fluxions sont indépendantes, et peuvent être déplacées d’une machine à l’autre pour amortir l’augmentation du trafic. L’équipe de développement peut commencer à développer avec la productivité de la boucle évènementielle. Et avec la transformation, elle peut itérer pour progressivement atteindre l’efficacité du pipeline.