# des réseaux sans fil dynamiques:

Axe: ComEx
Coordinateur : Michel MAROT
Objectif : Organisation de séminaire et échanges sur le thème des réseaux sans fil
Productions Scientifiques :
Financement Labex en : 2014/2015

Documents :

Présentation:
Ce groupe de travail se focalise sur les performances des réseaux sans fil, sur l'analyse de la QoS et la gestion de ressources dans le cas des réseaux dynamiques. Parmi ces types de réseaux sont considérés les réseaux ad-hoc, les réseaux mesh, les réseaux de capteurs, les réseaux hétérogènes, les réseaux véhiculaires, le Wireless-SDN, le sans-fil multisauts.... Les travaux sont menés dans des contextes technologiques et applicatifs pointus qui déterminent les contraintes des problèmes d’optimisation sous-jacents à l’allocation de ressources et exigent souvent une définition de la QoS spécifique. Les discussions porteront aussi sur les méthodes d'analyse de performance, la modélisation de la mobilité et l'impact de la mobilité sur ces systèmes, en particulier en termes de connectivité, de dimensionnement et de délais.

Le but de ce groupe de travail est d'être un lieu d'échanges sur cette thématique à travers la tenue de séminaires mensuels faisant intervenir à la fois les collègues du groupe et de leurs équipes ainsi que quelques chercheurs invités extérieurs.

Personnes concernées :
• SAMOVAR : Afifi Hossam, Marot Michel, Zeghlache Djamal
• PRISM : Barth Dominique, Fourneau Jean-Michel, Kloul Leila, Tohmé Samir
• LRI : Boukhatem Lila, Martin Steven
• LTCI : Chaudet Claude, Coupechoux Marceau, Labiod Houda
• CEA : Essafi Hassane, Janneteau Christophe, Petrescu Alexandru
• INRIA : Muhlethaler Paul
• SUPELEC : Tomasik, Joanna, Vèque Véronique

Sessions passées :

### VENDREDI 10 JUIN 2016 APRES-MIDI

VENDREDI 10 juin 2016 APRES-MIDI

Session du Groupe de Travail DigiCosme
"Performances, QoS et gestion de ressources des réseaux sans fil dynamiques"
Lieu : Salle 26, bâtiment 862 – NanoInnov
Avenue de la Vauve
91120 PALAISEAU
GPS : N. 48°42,7575', E. 02°11,5228')
Entrée libre

14h30-15h15: Mme Aroua Biri (Experte en stratégie Sécurité et Réseaux chez Suntory) – Titre : Les enjeux des grands groupes en termes de réseaux informatiques.

Résumé: Les réseaux informatiques sont le nerf névralgique des grands groupes qui permet la bonne circulation des données au sein des entreprises ainsi qu'avec les clients et partenaires. Ils sont alors confrontés à 3 grands enjeux:

- La gestion d'un nombre de plus en plus croissant de sites de part le monde avec un besoin impérieux en mutualisation
- La segmentation réseau des datacenters qui doit être business-friendly
- L'accompagnement efficace des fusions/acquisitions/séparation en termes de réseaux informatiques

Par ailleurs, nous évoquerons les outils suivants: Netflow et Algosec.

15h15-16h00: Mr Hatem Ibn Khedher (Institut Mines Télécom/Télécom SudParis) – Titre : OMAC: Optimal Migration Algorithm for Virtual CDN

Abstract: Content delivery network meets the modern virtualization techniques based on Software-Defined Networking (SDN) and/or Network Functions Virtualization (NFV). Therefore, virtual nodes can be easily migrated from one location to another. In this présentation, an intelligent migration algorithm for deciding the optimal placement destinations for virtual content delivery functions is proposed (OMAC). Then, it is implemented and evaluated. Several scenarios are considered to study the algorithm’s behavior and to quantify the impact of both network and system parameters.
Presentation : HATEM, AROUABIRI

### VENDREDI 20 MAI 2016 APRES-MIDI

Session du Groupe de Travail DigiCosme
"Performances, QoS et gestion de ressources des réseaux sans fil dynamiques"
Lieu :
Salle 26, bâtiment 862 – NanoInnov
Avenue de la Vauve
91120 PALAISEAU
(GPS : N. 48°42,7575', E. 02°11,5228')
Entrée libre

14h30-15h15: Mr. Seif Eddine Hammami (Institut Mines Télécom/Télécom SudParis)
Titre : Network planning tool based on network classification and load prediction

Abstract : Real Call Detail Records (CDR) are analyzed and classified based on Support Vector Machine (SVM) algorithm. The daily classification results in three traffic classes. We use two different algorithms, K-means and SVM to check the classification efficiency. A second support vector regression (SVR) based algorithm is built to make an online prediction of traffic load using the history of CDRs. Then, these algorithms will be integrated to a network planning tool which will help cellular operators on planning optimally their access network.

Keywords : CDR, Classification, SVM, K-means, Prediction, traffic Load, SVR, Network planning tool.

15h15-16h00: Mr Jun Zhang (Institut Mines Télécom/Télécom ParisTech)
Titre : Energy efficient routing in multi-layer femtocell networks

Abstract: We present an energy efficient routing algorithm for multi-layer femtocell networks. We consider a fourlayered architecture that consists users, femtocells, relays, and macro base stations. The traffic to/from users passes through this architecture and is aggregated from/to the Internet through gateways in the relay layer. The traffic demand from users changes from time to time, so that some relays can be put into sleep mode in non-peak time to save energy. We propose a simple and effective routing algorithm to decide routes and active relays, to satisfy user traffic demand and save energy. Simulation results show that our proposed method outperforms benchmark schemes.

Jun Zhang received his BEng (2002) in computer science and technology from Shanghai Jiaotong University, and Ph.D (2007) in computer science from Hong Kong University of Science and Technology. He was a research fellow in the Hong Kong City University (2007-2009), the Hong Kong Polytechnic University (2009-2011), a postdoctoral fellow in the Hong Kong University of Science and Technology (2011-2013), and currently a postdoctoral researcher in Telecom Paristech. His research interests include wireless multi-hop networks (ad hoc/sensor/mesh networks), wireless LAN and vehicular networks.

Presentation : Jun ZHANG, Seif Eddine HAMMAMI

### VENDREDI 11 MARS 2016 APRES-MIDI

VENDREDI 11 MARS 2016 APRES-MIDI

Session du Groupe de Travail DigiCosme
"Performances, QoS et gestion de ressources des réseaux sans fil dynamiques"
Lieu : Amphi 33, bâtiment 862 – NanoInnov
Avenue de la Vauve
91120 PALAISEAU
GPS : N. 48°42,7575', E. 02°11,5228')
Entrée libre

14h30-15h10: Mrs Wided Medjroubi (NEXT ENERGY, EWE-Forschungszentrum für Energietechnologie e. V.) – Titre : SciGRID: Derivation of an Open Source Transmission Network using OpenStreetMap Data

Abstract : Data is a crucial element in energy systems modelling which is relevant for political and economic decisions concerning renewable energies integration. Transmission network data is particularly relevant as there are hardly any complete and reliable datasets available. This applies also to the European transmission network. In fact, the lack of network data negatively impacts research activities especially in the sectors of renewable energy sources development and grid stability and expansion.

In this context, the focus of the SciGRID(1) project (started at the end of 2014) is to develop a free access, open source, open data and well documented European transmission network model. The SciGRID model uses the power data available in the OpenStreetMap (OSM)(2) database, which is available under the Open Database License (ODbL)(3). This license makes it possible to use the OSM data for our purposes and to share the derived SciGRID data under the same license. SciGRID is the first open dataset of the European transmission network.

SciGRID uses in particular power data in OSM represented by the so-called “power relations”. OSM relations are data elements representing a logical or a geographical relationship between its constituting members. In SciGRID, the OSM data is filtered for “power relations” and abstracted to result in a topological network model for the very high and high voltage levels (≥220 kV). Relevant information about the nodes and lines of the network, when available, are included in the SciGRID dataset (e.g. names of substations, electrical properties). The abstracted network is represented by two geo-referenced tables of the transmission network nodes (called vertices) and edges (called links). As of version v0.2 the SciGRID model covers the German transmission network and consists of 495 vertices and 825 links. It is planned to extend the SciGRID model to cover all European countries.

In this contribution, open data importance and relevance to energy system modelling will be presented and discussed. Details about the derivation of the SciGRID model and data will be highlighted.

15h10-15h50: J.G. Caputo and A. Knippel, INSA de Rouen – Titre : Oscillations of networks: finding soft nodes

Abstract: The graph wave equation is a simple linear model that can describe small electromechanical waves in power grids. It gives rise to a Fourier decomposition on normal modes so that it can be analysed in detail. In a previous study we defined soft nodes as nodes corresponding to a null component of an eigenvector. On these soft nodes, the system cannot be observed or controlled and any energy input or damping is ineffective. Some problems identified in the literature for real power grids seem related to our soft nodes. Then, two important questions arise: can one identify soft nodes by inspecting the network ? can one predict eigenvalues and eigenvectors of a given graph? We will provide partial answers to these questions and present new results on the classification of networks.

15h50-16h30: Nicolas Gensollen, Institut Mines-Télécom Télécom SudParis – Titre : Control of Prosumer Networks

Abstract: The ability to control a given network by dynamically injecting inputs offers ways to make sure that it stays in stable regions. In the case of smart grids, where end users exhibit complex behaviors and renewable production is quite unstable, control of the system is paramount. In this paper, we study the case of a network composed of entities called prosumers. These agents have the ability to both consume and produce according to external conditions. We first model and simplify the underlying dynamic of such network using a second order coupled oscillators network model. Under some conditions, the system synchronizes to a common frequency. However, in case of perturbations in the power distribution, the system might lose synchrony and require control to bring it back to the stable state. In this situation, control can be seen as energy absorbed or injected in the system at specific locations. Moreover, the power outputs of the prosumers are susceptible to change such that loads and generators are not fixed. In this context, it is important to select the right subset of nodes that yields, on average, the cheapest control in terms of energy. We use here the submodularity of gramian based metrics to select the control nodes, and we study how the drivers and the energy evolves with the power grid topology and parameters.

Presentation : SciGRID, Beamer, Talk

(1) www.scigrid.de. SciGRID is financed through the Ministry of Education and Research under the financing initiative “Zukunftsfähige Stromnetze” http://forschung-stromnetze.info/.
(2) www.openstreetmap.org
(3) www.opendatacommons.org

### VENDREDI 4 DECEMBRE 2015 APRES-MIDI

Lieu :
Amphi 33, bâtiment 862 – NanoInnov
Avenue de la Vauve
91120 PALAISEAU
(GPS : N. 48°42,7575', E. 02°11,5228')
Entrée libre

14h30-15h30: Tim Hall (National Institute of Standards and Technology - NIST, USA

Titre : Preserving Privacy in Spectrum Sharing Systems

There is a limited amount of spectrum available for use by wireless communications systems. Because of this, frequency bands that were reserved exclusively for government purposes, such as military and weather radar, are being opened up for sharing with commercial communications users. For example, in the United States, the 3550 – 3700 MHz band used by shipborne radar in coastal areas and fixed satellite systems (FSS) on land is being made available to both licensed and unlicensed users via centrally coordinated spectrum sharing. However, the spectrum coordination needed between the government incumbent and commercial users gives rise to several privacy concerns. I will introduce and motivate the spectrum sharing problem, present the architecture of a centrally-coordinated system for sharing and highlight the security and privacy threats. Following this, I will introduce obfuscation techniques along with metrics for evaluating their effectiveness and the tradeoff between privacy and spectrum efficiency.

Tim Hall is a researcher in the Wireless Networks Division of the Communications Technology Laboratory (CTL) at the U. S. National Institute of Standards of Technology (NIST). He received a PhD in Electrical Engineering from the University of Delaware, with a concentration in signal processing and communications. He spent five years at a small company developing software for scientific and engineering applications before coming to NIST in 1999. At NIST he has worked on modeling and simulation, wireless networks, cryptography, conformance testing and project management. Currently his focus is on spectrum sharing in the 3.5 GHz band, specifically spectrum occupancy analysis and prediction, operational security for the Spectrum Access System (SAS) and design and implementation of the environmental sensing capability (ESC).

Presentation : Preserving Privacy In Spectrum Sharing Systems

### MARDI 3 NOVEMBRE 2015 APRES-MIDI

Session du Groupe de Travail DigiCosme
"Performances, QoS et gestion de ressources des réseaux sans fil dynamiques"
Lieu : Salle du Conseil – L2S, SUPELEC
Plateau du Moulon
3, rue Joliot-Curie
91192 Gif-sur-Yvette cedex
(plan d’accès : http://www.supelec.fr/388_p_12022/plan-d-acces.html )
Entrée libre

14h00-15h00: Mr Jean-Charles Grégoire (INRS, Canada)
Titre : Communications A/V de qualité sans (?) infrastructure

Résumé : Nous assistons depuis quelques années à une transformation dans la nature de certaines communications audio-visuelles sur l'Internet: leur imbrication au sein d'environnements comme des plateformes sociales. Cette transition d'environnement dédié vers composante imbriquée a eu des effets notables sur la manière dont la qualité de service est appréhendée et gérée dans ces environnements, principalement dans des modèles « over the top », et soulève d'autres questions sur le lien avec les infrastructures de communication traditionnelles. Nous présentons ici la problématique des communications A/V OTT et discutons plus en profondeur deux éléments clés, à savoir les nouvelles architectures de service dans lesquelles elles sont déployées, et les approches de gestion et de substitution à la qualité de service. Nous ferons le point sur l'état de l'art en la matière ainsi que sur des travaux en cours à l'INRS.

Biographie: Le professeur Grégoire est diplômé de la Faculté polytechnique de Mons (Belgique). Il détient une Maîtrise en mathématiques de l'University of Waterloo (Canada) et un Doctorat en génie de l'Ecole polytechnique fédérale de Lausanne (Suisse). Il est présentement professeur à l'Institut national de la recherche scientifique (INRS), dans le secteur des télécommunications. Le professeur Grégoire poursuit des travaux de recherche sur les systèmes de communication répartis et leur implantation dans le contexte de l'Internet. Il a de nombreuses publications sur des sujets divers qui touchent à la sécurité, à la qualité des applications multimédia, aux réseaux d'accès et aux architectures de service sur l'Internet. A travers sa carrière, il a également entretenu des collaborations fructueuses avec diverses compagnies du secteur des télécommunications.

Presentation : Communications A/V De Qualité Sans (?) Infrastructure

15h00-16h00 : Koen de Turck, O2MR, LSS
Titre : Modulated Erlang loss models: How traffic correlation affects the square-root staffing rule

Abstract: In this talk, we revisit the classical question of how many servers must one provision in order to guarantee on the one hand a good quality of service to the customer (that is, a limited amount of blocked calls), while on the other hand ensuring an efficient operation of the system, with few idle servers. Since the celebrated work of Halfin and Whitt, we know that for a Poisson arrival stream and a large load \rho, the ideal number of servers must be around $\rho + \beta \sqrt{\rho}$, where $\beta$ is some hedge factor. This is the square-root staffing rule and the intuition behind it is that one must cater for at least the expected system contents $\rho$, but also provide some 'wiggle room' for common fluctuations around the mean. The hedge factor \beta represents the aforementioned tradeoff: the larger $\beta$, the better the quality of service but also the more expensive to the service provider. As we know, real world traffic often exhibits a large degree of correlation and hence the Poisson assumption is not really valid. Hence, we look at Markov modulated arrival streams, and speed them up at a different rate than we scale the load. We find three different regimes depending on the speed of the modulated chaiin, and a considerably altered staffing rule when said speed is slow.

Short bio: Koen De Turck obtained a master and a PhD in engineering from Ghent University, Belgium. Since July 2015, he is an assistant professor at CentraleSupélec, where he is a member of the lab Signaux et Systèmes (L2S). He develops and studies stochastic models for telecommunication networks in general and wireless networks in particular. His favorite tools include queuing theory, scaling techniques, large deviations and evolutionary game theory.

Koen De Turck, Supélec
Presentation : Modulated Erlang Loss Models: How Traffic Correlation Affects The Square Root Staffing Rule

### JEUDI 15 OCTOBRE 2015 APRES-MIDI

Session du Groupe de Travail DigiCosme
"Performances, QoS et gestion de ressources des réseaux sans fil dynamiques"
Lieu : Amphi Blondel – SUPELEC
Plateau du Moulon
3, rue Joliot-Curie
91192 Gif-sur-Yvette cedex
(plan d’accès : http://www.supelec.fr/388_p_12022/plan-d-acces.html )
Entrée libre
::
14h30-15h30: Ahmed E. Kamal, Iowa State University
Titre : Resilient Wireless Sensor Networks: the Case of Network Coding

This presentation considers the resilient delivery of data in wireless sensor networks, which flows from the sensor nodes to the sink. This data flow is transported using the many-to-one, or convergecast service mode. Traditional protection schemes are either resource-hungry like the (1+1) protection scheme, or introduce latency in detecting and recovering from failures, which interrupts the network operation like the (1:N) protection scheme.

This talk presents several contributions made by our group in developing network coding-based protection techniques in order to overcome the deficiencies of the aforementioned traditional schemes. A basic scheme, which applies to a restricted network topology will be introduced as an optimal solution. Then, the topology will be relaxed to include any practical wireless network topology, and the scheme will be generalized to apply to such topologies. It will be shown how to perform deterministic coding with {0,1} coefficients at intermediate sensor nodes, and how to perform decoding at the sink to recover data. Practical considerations for the implementation of those schemes will be considered.

Biography: Ahmed E. Kamal is a professor of Electrical and Computer Engineering at Iowa State University in the USA. He received a B.Sc. (distinction with honors) and an M.Sc. both from Cairo University, Egypt, and an M.A.Sc. and a Ph.D. both from the University of Toronto, Canada, all in Electrical Engineering. He is a Fellow of the IEEE and a senior member of the Association of Computing Machinery. He was an IEEE Communications Society Distinguished Lecturer for 2013 and 2014.

Kamal's research interests include cognitive radio networks, wireless networks, optical networks, and performance evaluation. He received the 1993 IEE Hartree Premium for papers published in Computers and Control in IEE Proceedings, and the best paper award of the IEEE Globecom 2008 Symposium on Ad Hoc and Sensors Networks Symposium.

Kamal is the chair of the IEEE Communications Society Technical Committee on Transmission, Access and Optical Systems (TAOS). He also chaired or co-chaired Technical Program Committees of several IEEE sponsored conferences including the Optical Networks and Systems Symposia of the IEEE Globecom 2007 and 2010, the Cognitive Radio and Networks Symposia of the IEEE Globecom 2012 and 2014, and the Access Systems and Networks track of the IEEE International Conference on Communications 2016. He is on the editorial boards of the IEEE Communications Surveys and Tutorials, the Computer Networks journal, and the Optical Switching and Networking journal.

Presentation : Survivability Of Wireless Sensor Networks: The Case Of Network Coding

### VENDREDI 25 SEPTEMBRE 2015 APRES-MIDI

Lieu :
Amphi 33, bâtiment 862 – NanoInnov
Avenue de la Vauve
91120 PALAISEAU
(GPS : N. 48°42,7575', E. 02°11,5228')

Entrée libre

Programme :

14h30-15h30: Luigi Aztori, University of Cagliari ; Multimedia Communications Laboratory of CNIT, Italy

Titre: Trustworthiness and navigability in the social Internet of Things
The integration of social networking concepts into the Internet of Things has led to the Social Internet of Things (SIoT) paradigm, according to which objects are capable of establishing social relationships in an autonomous way with respect to their owners with the benefits of improving the network scalability in information/service discovery. After an introduction of the SIoT paradigm, this talk focuses on two problems: trustworthiness management and friendship selection. As to the trustworthiness management two models are discussed: in the subjective model each node computes the trustworthiness of its friends on the basis of its own experience and of the opinion of the friends in common with the potential service providers; in the objective model, the information about each node is distributed and stored making use of a distributed hash table structure so that any node can make use of the same information. As to the friendship selection, the major principle is to consider its impact on overall network navigability. The proposed heuristics are based on local network properties and on their impact on the overall network structure in terms of number of giant components, average degree of connections, local clustering and average path length.

Luigi Atzori is Associate Professor at the Department of Electrical and Electronic Engineering at the University of Cagliari (Italy) and Research Associate at the Multimedia Communications  Laboratory of CNIT (Consorzio Nazionale Interuniversitario per le Telecomunicazioni).
L. Atzori research interests are in computer networking, with particular emphasis on service management for Internet of Things and in wireless sensor networks, and multimedia communications, with a focus on multimedia QoE and wireless video streaming. L. Atzori is senior member of IEEE, chair of the Steering Committee of the IEEE Multimedia Communications Committee (MMTC) and co-chair of the IEEE 1907.1 standard on “Network-Adaptive Quality of Experience (QoE) Management Scheme for Real-Time Mobile Video Communications”. He is the coordinator of the European Marie Curie Initial Training Network on QoE for multimedia services (www.qoenet-itn.eu), which involves ten European Institutions in Europe and one in South Korea. He has been the editor for the ACM/Springer Wireless Networks Journal and guest editor for the IEEE Communications Magazine, the Springer Monet Journal and the Elsevier Signal Processing:  Image Communications  Journal. He is member of the editorial board of the IEEE IoT, the Elsevier Ad Hoc Networks and the Advances on Multimedia journals. He served as a technical program chair for various international conferences and workshops. He served as reviewer and panellist for many funding agencies, including FP7, Cost Action, Italian MIUR and Regional funding agency.

Presentation : Trustworthiness And Navigability In The Social Internet Of Things

### VENDREDI 19 JUIN 2015 APRES-MIDI

Lieu :
Amphi 34, bâtiment 862 – NanoInnov,
Avenue de la Vauve
91120 PALAISEAU
(GPS : N. 48°42,7575', E. 02°11,5228')

Entrée libre

Programme :

14h00-14h45: Marco Fiore, CNR Italie

Titre: Road traffic modeling with an eye to networking applications

The performance of protocols and architectures for upcoming connected vehicles are commonly investigated by means of computer simulations, due to the excessive cost and complexity of large-scale experiments. Dependable and reproducible simulations are thus paramount to a proper evaluation of vehicular networking solutions. Yet, we lack today a reference dataset of vehicular mobility scenarios that are realistic, publicly available, heterogeneous, and that can be used for networking simulations straightaway. In this talk, we present several contributions to the development of such a reference dataset, including (i) original synthetic traces that are generated from reliable sources, (ii) validation methodologies, and (iii) assessments of the potential impact of the traces on networking studies.

Presentation : Road Traffic Modeling With An Eye To Networking Applications

14h45-15h30: Alexandre Mouradian, L2S Université Paris Sud

Titre: Study of Probabilistic Worst Case Inter-Beacon Delays Under Realistic Vehicular Mobility Conditions

Road safety applications are one of the main incentives to deploy vehicular networks. These applications rely on periodic message exchange among vehicles (known as beaconing). The beacon messages contain information about the environment which is used to perceive dangerous situations and alert the drivers. The inter-beacon delay is the time between two consecutive beacons received from a car. It is an essential parameter because, if this delay exceeds the application requirement, the application cannot accurately predict dangerous situations and alert the drivers on time. The worst case inter-beacon delay has thus to be bounded according to the application requirements. Unfortunately, a tight and strict bound is in fact very difficult to obtain for a real network because of the randomness of the collisions among beacons coming from: the unpredictable mobility patterns, random interferences, randomness of the MAC layer backoff, etc.

We propose to provide a probabilistic worst-case of the inter-beacon delay under realistic mobility using Extreme Value Theory (EVT). EVT provides statistical tools which allow to make predictions on extreme deviations from the average of a parameter. These statistical predictions can be made based on data gathered from simulation or experimentation. We first introduce the EVT technique. Then we discuss its application to the study of inter-beacon delays. Finally, we apply EVT on the results of extensive vehicular network simulation using a realistic mobility trace: the Cologne trace.

Presentation : Study Of Probabilistic Worst Case Inter Beacon Delays Under Realistic Vehicular Mobility Conditions

15h30-16h15: Michel Marot, Telecom SudParis

Titre: On the Maximal Shortest Path in a Connected Component in V2V

We consider a VANET (Vehicular Ad-hoc NETwork) in a simple lane, without infrastructure. The arrivals of vehicles are assumed to be general with any traffic and speed assumptions. The vehicles communicate through the shortest path. We present results on the probability distribution of the number of hops on the maximal shortest path in a connected component of vehicles. The general formulation is given for any assumption of road traffic. Then, it is applied to calculate the z-transform of this distribution for medium and dense networks in the Poisson case. Our model is validated with the Madrid road traces of the Universitat Polit\`ecnica de Catalunya. These results may be useful for example when evaluating diffusion protocols through the shortest path in VANET, where not only the mean but also the other moments are needed to derive accurate results.

Presentation : On The Maximal Shortest Path In A Connected Component In V2V

### VENDREDI 29 MAI 2015 APRES-MIDI

Lieu :
Amphi 34, bâtiment 862 – NanoInnov
Avenue de la Vauve
91120 PALAISEAU
(GPS : N. 48°42,7575', E. 02°11,5228')

Entrée libre

Programme :

14h00-15h00: Jim Roberts, IRT-SystemX

Titre : Multi-Resource Fairness: Objectives, Algorithms and Performance

Designing efficient and fair algorithms for sharing multiple resources between heterogeneous demands is becoming increasingly important. Applications include compute clusters shared by multi-task jobs and routers equipped with middleboxes shared by flows of different types. We show that the currently preferred objective of Dominant Resource Fairness (DRF) has a significantly less favorable efficiency-fairness tradeoff than alternatives like Proportional Fairness and our proposal, Bottleneck Max Fairness. We propose practical algorithms to realize these sharing objectives and evaluate their performance under a stochastic demand model. It is shown, in particular, that the strategyproofness property that motivated the choice of DRF for an assumed fixed set of jobs or flows, is largely irrelevant when demand is dynamic.

Presentation : Multi Resource Fairness: Objectives, Algorithms And Performance

--------------------------

15h00-16h00 : Aline Carneiro Viana, INRIA

Titre: Mobile Data Traffic Modeling: Revealing Temporal Facets

Todays’ smart handheld devices allow heterogeneous free data gathering of human surrounding environment and networking usage patterns anytime and anywhere. Hence, an unprecedentedly large amount of human sensory data (i.e., the Big Data era) can be collected and processed: opening ways to connect people, technology, and business. This big data implies advanced knowledge of humans’ behaviour and interactions at a planetary scale and can help tackle networking challenges when used correctly. In this presentation, I will briefly talk about my most recent works where I leverage behavior of networking users (in terms of interactions, mobility, or content generation) to improve the performance of networking solutions designed for data offloading or dissemination.

I will then provide more details about our work on user content behavior modeling: Measurement-driven modeling of mobile data traffic usage of smartphone subscribers, which was based on the use of a large-scale dataset collected from a major 3G network in a big metropolitan area. Our main outcome is a synthetic measurement based mobile data traffic generator, capable of imitating traffic-related activity patterns of different categories of subscribers and time periods of a routinary normal day in their lives. Broadly, our observations bring important insights into network resource usage.

Presentation : Mobile Data Traffic Modeling: Revealing Temporal Facets

### VENDREDI 6 FÉVRIER 2015

Lieu :
AMPHI 34, BÂTIMENT 862 – NANOINNOV
Avenue de la Vauve
91120 PALAISEAU
GPS : N. 48°42,7575', E. 02°11,5228'

Entrée libre

Programme :

Titre : RESOURCE ALLOCATION AND RELIABILITY WITHIN CLOUD’S BACKBONE NETWORK

In this talk, I will address the resource allocation problem of Network as a Service (NaaS) within Cloud’s backbone. The main objective is to maximize the acceptance rate of virtual network requests while maximizing the quality of service and reliability of end-users. In doing so, the turnover of Cloud provider will grow up. I will detail three main resource provisioning strategies denoted by i) PR-VNE based on bee colony meta-heuristic, ii) CG-VNE based on artificial potential game theory and iii) BR-VNE based Monte-Carlo tree search.

Présentation : Resource Allocation And Reliability Within Cloud’s Backbone Network

10H30H-11H30 : NICOLAS THOMAS, UBUNTU

Titre: DESIGNING FOR SCALE AT DEVOPS SPEED DELIVERED: JUJU
This presentation will be made around a live demo on stage of the amazing capabilities Juju provides to deploy and operate in Cloud environment or to deploy the Cloud itself. http://juju.ubuntu.com 3 innovative concept to truly take advantage of the cloud technologies and API. Ready to drop pet for cattle, Juju is your Shepherd.

Présentation : JUJU OVERVIEW

11H30H-12H30 : FRANÇOIS FRÉDÉRIC OZOG, 6WIND

Titre: SCALE-UP STRATEGY FOR VCDN OR HOW TO GET UP TO 8X CDN CAPACITY ON THE SAME HARDWARE
La distribution de contenu statique (images, css, scripts...) et de média (films, audio...) peut dès aujourd'hui bénéficier de technologies qui permettent de multiplier la capacité d'un seul serveur tout en virtualisant l'application de distribution. 6WIND présentera des produits et "proof of concepts" qui permettent d'accélérer 10x la pile TCP/IP dans le guest, 8x l'accès au stockage et 10x la pile TCP/IP dans le host.

Deux benchmarks de technologies 6WIND serviront de fil conducteur (à notre connaissance, records mondiaux sur un seul serveur): d’une part 240Gbps de contenu web transmis sur le réseau à partir de 6,5M de requêtes HTTP/s avec 100M de connections simultanées (page moyenne de 4KB) et d’autre part 160Gbps de contenu stocké en Flash (approximativement 5MIOPS de 4KB) relayés sur le réseau.

Enfin, l'état d'avancement du work item ETSI IFA002 qui traite des interfaces d'accélération des VNF sera présenté. Ce work item a été initié conjointement par Orange et 6WIND.

Présentation : SCALE UP STRATEGY FOR VCDN

### VENDREDI 21 NOVEMBRE 2014 APRES-MIDI

Lieu :
Amphi 34, bâtiment 862 – NanoInnov
Avenue de la Vauve
91120 PALAISEAU
GPS : N. 48°42,7575', E. 02°11,5228'

Entrée libre

Programme :

14h-15h:Amine ADOUANE, Université de Versailles St-Quentin-en-Yvelines
Titre Game Theoretic Framework for Inter-Cell Interference Coordination

The exponential growth in the number of communications devices over the past decade has set out new ambitious targets to meet the ever-increasing demand for user capacity in emerging wireless systems. However, the inherent impairments of communication channels in cellular systems pose constant challenges to meet the envisioned targets. High spectral reuse efficiency was adopted as a solution to higher data rates. Despite its benefits, high spectral reuse leads to increased interference over the network, which degrades performances of mobile users with bad channel quality. To face this added interference, OFDM (Orthogonal Frequency Division Multiplexing) is used for the new 4th generation network. Thanks to its orthogonality OFDM eliminates the intra-cellular interference, but when the same resources are used in two adjacent cells, the inter-cell interference becomes severe. To get rid of the latter, several methods for Inter-Cell Interference Coordination (ICIC) have been proposed. ICIC allows coordinated radio resources management between multiple cells. The eNodeBs can share resource usage information and interference levels over the X2 interface through LTE-normalized messages. Non-cooperative game theory was largely applied were eNodeBs selfishly selects resource blocks (RBs) in order to minimize interference.

In this talk, we focus on ICIC for the downlink of a cellular OFDMA system in the context of the SOAPS (Spectrum Opportunistic Access in Public Safety) project. This project addresses low layers protocols issues for Broadband Services provision by PMR (Private Mobile Radio) systems using LTE technologies with particular focus on the improvement of frequency resource scheduling. Hence, our first work addresses the problem of downlink ICIC where the resource selection process is apprehended as a load balancing game for which we propose a fully decentralized algorithm. We adapt a stochastic version of a best-response dynamics algorithm to attain the pure Nash equilibria of the modeled game. Each eNodeB strives to select a pool of favorable resources with low interference based on local knowledge only. Proof of convergence is provided, and the efficiency of the tailored algorithm is proven through extensive simulations. In our second work, the ICIC issue was treated through adequate power allocation on RBs. The power level selection process of RBs is apprehended as a sub-modular game and a semi distributed algorithm based on best response dynamics is proposed to attain the NEs of the modeled game. Based on local knowledge conveyed by the X2 interface, each eNodeB will first select a pool of favorable RBs with low interference. Second, each eNodeB will strive to fix the power level adequately on those selected RBs realizing performances comparable with the Max Power policy that uses full power on selected RBs while achieving substantial power economy.

Présentation : GAME THEORETIC FRAMEWORK FOR INTER CELL INTERFERENCE COORDINATION

15h-16h : André-Luc BEYLOT, ENSEEIHT
Titre: Optimisation de bout-en-bout du démarrage des connexions TCP

Les protocoles de bout-en-bout tels que TCP souffrent lorsque l'un des liens présente des délais importants ce qui est par exemple le cas des communications par satellite. Nous montrons dans un premier temps dans cet exposé que les nouvelles versions de TCP telles que Compound ou Cubic améliorent sensiblement les performances pour les connexions longues mais restent toujours faibles pour les connexions courtes qui constituent encore de nos jours la majeure partie des communications.

Notre proposition se focalise donc sur le démarrage des connexions TCP. Une tentation forte est d'augmenter la fenêtre initiale même si cette proposition est controversée dans le cas de réseaux congestionnés. Nous suggérons alors d'augmenter la fenêtre initiale mais d'espacer les emissions dans cette première partie.

Nous montrons l'intérêt de notre proposition qui améliore sensiblement les performances et pas uniquement dans le cas d'étude initialement envisagé. Ces études ont d'abord été menées à l'aide de modèles mathématiques et de simulations.

La dernière partie de notre exposé porte sur l'implantation en vraie grandeur de notre proposition. Cette dernière nous a permis d'observer des phénomènes non pris en compte dans les simulateurs et de raffiner alors notre proposition.

Mots-clés : TCP, performances, implantation

Présentation : Understanding Cooperation Behavior In Information Dissemination In Vehicular Networks

### VENDREDI 10 OCTOBRE 2014 APRES-MIDI

Lieu :
Amphi 34, bâtiment 862 – NanoInnov
Avenue de la Vauve
91120 PALAISEAU

Entrée libre

Programme

14h-15h: Naila BOUCHEMAL, Université de Versailles St-Quentin-en-Yvelines

Titre : MAC-LTE Scheduler Modeling and Performance Evaluation in LTE Network

Résumé : Long Term Evolution (LTE) is the most recent evolution of mobile phone standards; it has been proposed to provide higher throughput and better spectral efficiency. However with the increasing of services applications supported by each device in LTE networks, the resources sharing function is one of the key challenging issues. In this context, Logical Channel Prioritization (LCP) is referred. In this paper, we propose a mathematical model and performance evaluation of the Medium Access Control (MAC) layer scheduling algorithm while considering the source traffic characteristics, thus an original applications mapping. Our study highlights the impact of the Radio Resource Control (RRC) configuration on the overall performance during the Transport Block (TB) construction. Our analysis is based on a numerical study of a discrete time Markov chains and validated by an extensive simulation runs.

Presentation : MAC LTE Scheduler Modeling And Performance Evaluation In LTE Network

--------------------------

15h-16h : Jun ZHANG, Institut Mines-Télécom

Titre: Evaluation of Cooperation Behavior in Information Dissemination in Vehicular Networks

Résumé: Data diffusion in wireless vehicular networks relies on multi-hop relaying. In nature, relaying process in distributed networks is a cooperative act. We investigate the evolution of cooperation incentive in information dissemination in vehicular networks. In such networks, critical information, such as traffic jamming status, is broadcasted between vehicles. Each node (vehicle) in the network may choose two possible strategies: cooperation or defection. By cooperation, a node benefits its neighbors by broadcasting useful information, but costs itself by bandwidth utilization. By defection, a node can receive information from its neighbors without any cost. However, if all nodes defect, the system is trapped into a prisoner dilemma situation. We model the behavior of each node via evolutionary game theory (EGT), and present an EGT-based information dissemination scheme (EGID). The EGID scheme is evaluated from both theoretical analysis, and event driven simulation.

Presentation : Understanding Cooperation Behavior In Information Dissemination In Vehicular Networks

### JEUDI 18, VENDREDI 19 SEPTEMBRE 2014

Workshop RA5G and
Digicosme RESEARCH ON NETWORK ARCHITECTURE AND MOBILITY MANAGEMENT IN 5G MOBILE SYSTEMS
in collaboration with Digicosme GT Perf/QoS/sans-fil dynamiques,
supported by Campus France, Digicosme and CEA at CEA Nano-Innov, France.

--------------------------
Programme:
Thursday, September 18th:
• welcome croissants, hall near amphi 33 building 862, 10h00.
• workshop RA5G, amphi 33 building 862 - 10h30-12h00
• "VIN-based namespace for Evolutionary Future Vehicular Internet", Sofiane Imadali, CEA.
• workshop RA5G, amphi 33 building - 14h30-16h30
• "Research on Mobility and Network Architecture for 5G Systems", Haneul Ko, Korea University. - 14h30-15h15
• coffee break
• "Research on Collaborative Content Download in Mobile Collaborative Community", Insun Jang, Korea University. - 15h45-16h30

Friday, September 19th:

-----------------

Title: VIN6: a VIN-based namespace for Evolutionary Future Vehicular Internet Speaker: Sofiane Imadali, CEA.

Abstract: Vehicle communications are becoming increasingly popular thanks to car manufacturers and Public Transport Authorities investments. Standard development bodies (IEEE, C2C, ETSI, and ISO) introduced protocol stacks supporting Safety-related and non-safety related use cases. This talk focuses on the IPv6 layer, common to all SDOs stacks.

In the context of Future Internet and Locator/Identifier split paradigm, we propose to study the integration of vehicular communications in an evolutionary manner through the Vehicle Identifcation Numbers (VIN) namespace. In particular, we define the VIN-based IPv6 addressing and discuss its benefits for end-to-end services and its compatibility with the LISP approach.

On the other hand, dynamic IPv6 addressing and routing configuration in vehicular networks is another important challenge attracting a fair amount of attention. Early proposals adapted fixed-infrastructure and MANET models and thus inherited their latency and overhead. Later, researchers relaxed some of the often restrictive assumptions (e.g., Router Advertisement TTL extension) but still focused on certain limited scenarios. Along the Future Internet line of research, this presentation poses the terms of this problem in the IP-based vehicular communications area and aims at giving one solution space instance based on the Vehicle Identification Numbers namespace. In this presentation, (1) a comprehensive and detailed tutorial of the main approaches is presented. (2) The Future Internet paradigm as applied to vehicular networking, specifically through VIN namespace for group and infrastructure communications is introduced. (3) An analytical parameterized model to analyze and evaluate the proposals that fit best our communication paradigm is also presented.

--------------------------
Title: Research on Mobility and Network Architecture for 5G Systems
Speaker: Haneul Ko, Korea University

Abstract: Handover is a procedure that transfers an ongoing call from one cell to another as the user moves through the coverage area of a cellular system. In LTE/LTE-A networks, the data path switching is the default handover procedure. However, the data path switching has some problems such as high signaling overhead to core network entities and causing high delay jitter. The small coverage and massive deployment of femtocell intensify these problems. To solve this problem, important work is conducted in the literature. In this presentation, (1) Previous works are summarized to solve the problems of the data path switching and (2) We suggest optimized and distributed data packet forwarding scheme by using Markov decision process (MDP) to attain the optimal handover performance in LTE/LTE-A networks. We also introduce recent works on the network architecture for 5G systems.

--------------------------
Speaker: Insun Jang, Korea University

Abstract: Mobile collaborative community (MCC) is an emerging technology where multiple mobile nodes (MNs) conduct a job (e.g., large content download) in a cooperative manner.

--------------------------
Title: Research Activity and Direction in Mobile Network and Communications Lab, Korea University
Speaker: Sangheon Pack, Korea University

Abstract: In this talk, I will introduce the current research activities in Mobile Network and Communications Lab, Korea University. Specifically, four research categories:
1) Future Networking Architecture for Mobility Management,
2) Software-Defined Networking (SDN) and Network Function Virtualization,
3) Emerging Mobile Services such as mobile cloud and mobile social
networking, and
4) Next-Generation WLANs and WMNs, are introduced and several
collaboration topics are discussed.

In addition, the current status for the joing co-research program between CEA LIST and Korea University/Sangmyung University, "Research on Network Architecture and Mobility Management in 5G Mobile Systems", is reported and future directions will be discussed.

--------------------------
Title: how to reduce operator costs for increasing Internet affordability
Speaker : Yvon Gourhant, Orange

The emergence of Internet access and advanced wireless technologies has its limitations across the globe, i.e. today there exist several rural regions, especially in developing countries, that do not afford Internet connectivity.

In this talk, we will present two solutions that reduce operator costs for providing Internet affordable for all.

The first solution is a new business model and the design of a cost-effective wireless network architecture that aims at providing Internet in fix-usage within those countries. We claim that with few design changes to the 3GPP architecture, it is possible to extend Internet connectivity within suburban and rural areas by deploying numerous hotspots based on sharing tasks and revenues with local actors.

The second part of the talk is about dynamic sharing backhaul resources between operators in order to provide network survivability without investing extra-resources for setting up backup paths, but still keeping the competition at network level between operators. Our contribution is twofold. First, we will present multi-operator cooperative routing based on SDN (Software Defined Network) over maximally disjoint paths for the survivability of wireless backhaul. Second, we will deal with the problem of placing multiple centralized SDN controllers, among multiple network topologies, so as to maximize the resilience and scalability of such networks- within the bounds of convergence delay.

### VENDREDI 13 JUIN 2014 APRES-MIDI

Session du Groupe de Travail DigiCosme

Lieu :

Amphi 33 – NanoInnov
Avenue de la Vauve
91120 PALAISEAU
GPS : N. 48°42,7575', E. 02°11,5228'

Entrée libre

Programme:

14h-15h : Anthony Busson, Université de Lyon 1

Titre: Modèle de géométrie stochastique pour le CSMA
Résumé: Les noeuds d'un réseau ad hoc partage en générale le même canal Wi-Fi. Ce canal peut être utilisé par plusieurs noeuds en même temps tant que leur distance est suffisamment grande afin d'éviter que les interférences soient trop importantes. Cet exposé présente des modèles spatiaux (à deux dimensions) et des modèles sur la ligne (pour les VANETs) qui vise à estimer cette réutilisation spatiale du medium. Nous montrerons que la capacité du réseau ad hoc est étroitement liée à ce phénomène."

Presentation : Modèle De Géométrie Stochastique Pour Le CSMA

15h-16h : Stéphane Pomportes, ESIEE-Amiens

Titre : Les modèles de mobilité dans l’évaluation de performances des protocoles de communication

Résumé : l’évaluation de performances est une étape indispensable de la conception d'un protocole de communication et permet entre autres de savoir si la solution proposée apporte une réelle plus value par rapport à l'existant. Généralement réalisées par simulation ces évaluations sont tributaires de la capacité de l'environnement de simulation à reproduire les contraintes d'un environnement réel. Or, si des phénomènes physiques tels que la propagation des ondes ou les interférences électromagnétiques sont relativement bien compris et modélisés, ce n'est pas forcément le cas pour le déplacement des unités dans un réseau dynamique.

Au cours de cet exposé, nous ferons tout d'abord un tour d'horizon des principaux modèles de mobilité existant afin de mieux comprendre le rôle de chacun d'entre eux. Nous verrons ensuite comment les propriétés intrinsèques de certains modèles peuvent influencer de manière inattendue l'évaluation de performances des protocoles.

Presentation : Modèles De Mobilité Dans L’évaluation De Performances Des Protocoles De Communication

16h-17h : Daniel Popa, ITRON
Titre : Utilisation des technologies de communications dans les réseaux « smart grid » à grande échelle

Résumé :
• Présentation d’Itron
• Présentation des produits et solutions d’Itron pour les réséaux « smart grid » et au-delà (marchés verticaux)
• Présentations des technologies de communications: passé, présent et futur
• Défis technologiques et comment la recherche peut aider à relever ces défis

### VENDREDI 16 MAI 2014 APRES-MIDI

Session du Groupe de Travail

Lieu :
Amphi 34 – NanoInnov
Avenue de la Vauve
91120 PALAISEAU
(GPS : N. 48°42,7575', E. 02°11,5228')

Programme:

14h-15h : Joanna TOMASIK, Professeur à SUPELEC

Titre : Coloration de graphes au service de la sécurité nationale : coloration multiple et évaluée sur des graphes d’interférence

Résumé : Cet exposé présentera un problème d'allocation de ressources avec des contraintes de coloration dans des graphes modélisant les possibilités d'interférence au sein d'un réseau PMR (Private Mobile Radio), utilisé par les forces de l'ordre, l'armée.

Presentation : Coloration De Graphes Au Service De La Sécurité Nationale : Coloration Multiple Et évaluée Sur Des Graphes D’interférence

15h-16h : Sofiane Imadali, PhD candidate, CEA LIST, Communicating Systems Laboratory

Title: VIN6: a VIN-based namespace for Evolutionary Future Vehicular Internet

Abstract: Dynamic IPv6 addressing and routing configuration in vehicular networks is an important challenge that has attracted a fair amount of attention recently. Early proposals adapted fixed-infrastructure and MANET models and thus inherited their latency and overhead. Later, researchers relaxed some of the often restrictive assumptions (e.g., Router Advertisement TTL extension) but still focused on certain limited scenarios. Very recently, in the wake of the emerging concept of Future Internet, a general questioning arose on whether one naming and addressing model suits every network topology. Along this line of research, this presentation poses the terms of this problem in the IP-based vehicular communications area and aims at giving one solution space instance based on the Vehicle Identification Numbers namespace. In this presentation, (1) a comprehensive and detailed tutorial of the main approaches is presented. (2) The Future Internet paradigm as applied to vehicular networking, specifically through VIN namespace for group and infrastructure communications is introduced. (3) An analytical parameterized model to analyze and evaluate the proposals that fit best our communication paradigm is also presented. Depending on the audience, aspects related to privacy, large-scale deployment and revolutionary approaches (CCN-based) might be discussed.

Presentation : VIN6: A VIN Based Namespace For Evolutionary Future Vehicular Internet