Temporal verification in secure group communication system design

The paper discusses an experience in using a real-time UML/SysML profile and a formal verification toolkit to check a secure group communication system against temporal requirements. A generic framework is proposed and specialized for hierarchical groups

Projet CANet : un système de suivi de personnes à mobilité réduite grâce à leur canne de marche

National audienceLe projet CANet (CAne NETwork) a été mis en place en 2011 dans le but de répondre à une problématique sociétale tout en offrant l'opportunité à différents enseignants et enseignants-chercheurs de compétences variées et complémentaires de se regrouper autour d'un projet associant un volet recherche pluridisciplinaire à des activités pédagogiques pour nos étudiants d'IUT

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Modèles et services logiciels pour le travail collaboratif

This presentation synthesizes our main contributions in the framework of design of services and protocols for distributed collaborative systems. The first part presents our framework, the collaborative work, by taking the distributed systems viewpoint. The main advances and evolution trends of collaborative systems are studied, analyzed and classified. The main models of session are presented, analyzed, compared and classified. Then, the main existing session management systems are analyzed and compared. The second part presents our contributions for modeling collaborative sessions. The main elements that compose a collaborative sessions are firstly presented. The proposed session model id described and compared to other formalisms encountered. The detailed contributions are composed of implementation and use of the session model proposed. The third part presents the management of collaborative sessions. The proposed management service is described. Its characteristics are compared with other existing session management service characteristics. At end, the contributions are detailed in the domain of formal design and implementation of session management services and more generally collaborative services.Cet exposé synthétise nos principales contributions dans le cadre de la conception de services et de protocoles pour les systèmes distribués collaboratifs. La première partie présente le cadre de notre travail, le travail collaboratif, vu essentiellement selon l'angle de l'informatique répartie. Au travers d'une étude, analyse et classification, nous mettons en évidence, sous forme de bilan, les principales avancées et tendances d'évolution des systèmes collaboratifs. Nous présentons une analyse et une classification des principaux modèles de session rencontrés, que nous comparons et classifions. Finalement, nous procédons à une analyse et une comparaison des principaux gestionnaires de sessions existants. La seconde partie décrit nos contributions en terme de modélisation de sessions collaboratives. Après avoir décrit les principaux éléments qui composent une session collaborative, nous décrivons le modèle de session que nous avons proposé et nous le positionnons vis-à-vis des autres formalismes. Nous terminons par nos contributions détaillées pour l'implantation et l'utilisation de notre modèle de session. La troisième partie traite de la gestion des sessions collaboratives. Nous décrivons le service de gestion de session que nous avons proposé et nous comparons ses caractéristiques à celles des autres gestionnaires. Finalement, nos présentons le détail de nos contributions dans les domaines de la conception formelle et de l'implantation des services de gestion de session, et plus généralement de services collaboratifs

Conception de services et de protocoles pour la gestion de groupes coopératifs

Cooperative work is a domain that studies work of user groups in a general way. Its finality is the design of groupware, software sets that contain tools, applications and platforms for supporting the activities of user groups. The management of these groups and the information exchanges between their members require the definition of new communication services and protocols adapted to the needs of cooperative agents. Work presented inside this dissertation consist in defining, conceiving and managing the structuration of cooperative groups. A model based on graphs has been proposed based on the data sharing to represent the relationships between the different members of a cooperative group. From this model, a service has been defined to manage the entry and exit inside cooperation of the cooperative agents. An underlying communication protocol has been specified using the formal specification language Estelle. The proposed protocol has been verified using the Petri net environment VAL and has been implemented with the C language inside an UNIX environment from the generated Estelle code. An extension of this work allows the formation of private conversation subgroups (PCSs) that are dynamic subgroups created inside cooperations. Another protocol specified in Estelle has been proposed to manage the formation of PCSs and their evolution inside cooperation. In parallel with the group structuration, a study of the data that can be exchanged between cooperative agents has led to the definition of a service that manages data dependencies. This service, specified also in Estelle, allows to create, suppress or modify dependencies between data, and communicates the value changes to the set of dependent data.Le travail coopératif est un domaine qui étudie le travail de groupes d'utilisateurs de façon générale. Sa finalité est la conception de collecticiels, ensembles logiciels qui contiennent les outils, les applications, et les plate-formes qui supportent les activités de groupes d'utilisateurs. La gestion de ces groupes et les échanges d'information entre leurs membres nécessitent la définition de nouveaux services de communication adaptés aux besoins des agents en coopération. Les travaux menés dans ce mémoire ont consisté à définir, à concevoir et à gérer la structuration des groupes coopératifs. Un modèle à base de graphes a été proposé à partir du partage de données, pour représenter les relations entre les divers membres d'un groupe coopératif. A partir de ce modèle, un service pour l'entrée et la sortie en coopération des agents coopérants a été défini. Un protocole de communication sous-jacent a été spécifié en utilisant le langage de description formelle Estelle. Le protocole proposé a été vérifié en utilisant l'environnement à base de réseaux de Petri VAL, puis a été implanté en langage C sous UNIX à partir du code Estelle généré. Une extension de ce travail permet la formation d'apartés qui sont des sous-groupes très dynamiques créés à l'intérieur de la coopération. Un autre protocole spécifié en Estelle a été proposé pour gérer la formation de ces apartés et leur évolution au sein de la coopération. En plus de la structuration des groupes, une étude des données qui peuvent être échangées entre des agents coopérants a mené à la définition d'un service de gestion des dépendances de données. Ce service, spécifié également en Estelle, permet de créer, supprimer ou modifier des dépendances entre données, et répercute les modifications de valeurs vers l'ensemble des données dépendantes

An Effective Location-Based Alert Messages Dissemination Scheme for Software Defined Vehicular Networks

International audienceSoftware Defined Networking (SDN) is considered as a key paradigm for future vehicular networks and its adoption may pave the way to novel approaches to support emerging and legacy ITS services, such as Alert Message (AM) dissemination. Historically, to meet the low dissemination delay requirements and full vehicle coverage, Vehicular Ad-hoc NeTworks (VANETs) were considered as the underlying assumption of most proposed AM dissemination schemes. With SDN, vehicular-to-infrastructure (V2I) links are a viable alternative that adds to Vehicle-to-vehicle (V2V) links. Moreover, a global view of the network at a centralized controller complemented with information on vehicles and their route helps to adjust the dissemination procedure to improve its performance and efficiency. In this paper, we propose a location-based AMs dissemination scheme that combines V2I broadcasts with V2V rebroadcasts in order to provide a low delivery delay, very limited collisions, high information coverage with insignificant signaling and network overhead. The originality of our scheme stands in the selection process of V2V rebroadcasts which is based on vehicles’ location with respect to predefined rebroadcast points selected by the controller. Our proposal is evaluated and compared to legacy techniques. It shows significant improvements in delivery delays and network resource utilization

LAMD: Location-based Alert Message Dissemination scheme for emerging infrastructure-based vehicular networks

International audienceRequiring low dissemination delays and thorough vehicles coverage in the vicinity of an emergency event, Vehicular Ad-hoc NETworks (VANETs) were considered as the most adapted communication network to support alert messages dissemination. With the advent of Cooperative ITS services, emerging vehicular networks are expected to increasingly rely on Vehicle to Infrastructure (V2I) communication links, which are expected to be nominally available, with some transient and time-limited connectivity losses. The presence of V2I links paves the way to centralized network control, which can leverage vehicle-related and contextual information provided by the cloud to make more informed decisions. This paper proposes an effective alert message dissemination procedure called LAMD (Location-based Alert Messages Dissemination) for emerging vehicular networks that combines V2I broadcasts with selected V2V (Vehicle to Vehicle) rebroadcasts. The originality of our scheme lies in the selection process of V2V rebroadcasts, which is based on vehicles’ location regarding predefined rebroadcast points selected by a centralized controller. This leads to very limited collisions, low delivery delays, and high information coverage with insignificant signaling and network overhead compared to legacy VANET based dissemination techniques

Q-Learning Relay Placement for Alert Message Dissemination in Vehicular Networks

International audienceAlert message (AM) dissemination is a fundamental yet challenging issue in vehicular networks, as it relies on wireless transmissions in a highly mobile, potentially dense, and changing environment. Emerging network infrastructure-based vehicular networks are being considered as an alternative to Vehicular Ad-hoc NETworks (VANETs) for alert message dissemination. Indeed, assuming that Vehicle to Infrastructure (V2I) communication links are nominally available, with some transient and time-limited connectivity losses, recent alert message dissemination schemes primarily rely on V2I links to widely broadcast AMs. Vehicle to Vehicle (V2V) rebroadcasts performed by some selected relay vehicles located within pre-computed rebroadcast zones are then used to ensure the full dissemination within an area of interest. This paper focuses on rebroadcast zones placement. It proposes a Q-learning-based method that computes the minimum number and optimal locations of rebroadcast zones. From these computed zones, the combination of V2I broadcasts with V2V rebroadcasts allows the delivery of AMs in a whole area, even in the presence of locations with poor wireless connectivity. The performance results show that high information coverage and low delivery delays are achieved with our proposed Q-learning based placement. Useless duplicate rebroadcasts and collisions are also avoided, saving network resources

Déploiement sensible au contexte et reconfiguration des applications dans les sessions collaboratives

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

Adaptation d'architectures logicielles collaboratives dans les environnements ubiquitaires (contribution à l'interopérabilité par la sémantique)

Ce travail de thèse explore la conception d'applications collaboratives destinées a être exécutées dans des environnements ubiquitaires. Les applications collaboratives fournissent des moyens pour que des utilisateurs organisés dans des groupes puissent coopérer afin d'effectuer une tâche commune. Jusqu'à présent, ces applications ont été conçues pour une utilisation avec des systèmes de type "bureau". Dans ce travail nous proposons de faire profiter ces applications des possibilités offertes par les environnements issus de l'informatique ubiquitaire, notamment la sensibilité au contexte et l'adaptation. En premier lieu, un modèle sémantique de la collaboration, appelé GCO, est proposé afin de permettre l'expression des besoins de collaboration indépendamment du domaine d'application. Ce modèle est une ontologie de la collaboration incorporant des règles permettant d'effectuer d'inférences pour déduire un schéma de déploiement à partir des besoins de collaboration. En deuxième lieu, une approche de modélisation est proposée afin de faciliter la conception d'applications collaboratives ubiquitaires. Cette approche se base sur une décomposition multi-niveaux permettant la mise en œuvre d'une adaptation de l'architecture du système aux changements du contexte haut niveau (exigences de l'application) et bas niveau (contraintes liées aux ressources). Ensuite, le framework FACUS, qui est une implantation de l'approche utilisant GCO comme modèle pivot pour l'interopérabilité entre les exigences et les contraintes, est proposé. Enfin, FACUS est évalué tant du point de vue fonctionnel que de celui des performances, montrant la faisabilité de notre approche.This work explores the design of collaborative applications for ubiquitous environments. Collaborative applications support the cooperation of groups of users that want to achieve a common goal. Until now, collaborative applications have been designed for "desktop" systems. This work proposes the use collaborative applications in ubiquitous computing environnements, which offer new characteristics such as context awareness and adaptation. Firstly, a semantic model of collaboration, called GCO (Generic Collaboration Ontology), is proposed. This model allows expressing collbaoration needs independently of the application domain. Secondly, a modeling approach is proposed for the design of collaborative ubiquitious applications. This approach is based on a multi-layer decomposition that allows implementing the adaptation of the system's architecture to changes in the context. These changes can be high-level (application requirements) and/or low-level (resource constraints). Then, the FACUS framework, that implements the approach using GCO as pivot model for the interoperation of requirements and constraints, is proposed. Finally, FACUS functionalities and performances are evaluated, thus showing the feasibility of the approach.TOULOUSE1-BU Arsenal (315552103) / SudocSudocFranceF