Survey on Data-Centric based Routing Protocols for Wireless Sensor Networks

The great concern for energy that grew with the technological advances in the field of networks and especially in sensor network has triggered various approaches and protocols that relate to sensor networks. In this context, the routing protocols were of great interest. The aim of the present paper is to discuss routing protocols for sensor networks. This paper will focus mainly on the discussion of the data-centric approach (COUGAR, rumor, SPIN, flooding and Gossiping), while shedding light on the other approaches occasionally. The functions of the nodes will be discussed as well. The methodology selected for this paper is based on a close description and discussion of the protocol. As a conclusion, open research questions and limitations are proposed to the reader at the end of this paper

Model-based, event-driven programming paradigm for interactive web applications

Applications are increasingly distributed and event-driven. Advances in web frameworks have made it easier to program standalone servers and their clients, but these applications remain hard to write. A model-based programming paradigm is proposed that allows a programmer to represent a distributed application as if it were a simple sequential program, with atomic actions updating a single, shared global state. A runtime environment executes the program on a collection of clients and servers, automatically handling (and hiding from the programmer) complications such as network communication (including server push), serialization, concurrency and races, persistent storage of data, and queuing and coordination of events.National Science Foundation (U.S.) (Grant CCF-1138967)National Science Foundation (U.S.) (Grant CCF-1012759)National Science Foundation (U.S.) (Grant CCF-0746856

Seamless Distribution of Data Centric Applications through Declarative Overlays

BDA 2011: 27èmes journées Bases de Données AvancéesWe present an approach based on peer-to-peer overlays which allows to distribute seamlessly data centric applications defined by queries over a centralized database. We consider applications in which the users have access to views, which contain horizontal fragments of the data of interest to them. The peer-to-peer overlays are defined by simple declarative programs in the Netlog language. The communication relies on implicit addresses, which can be evaluated on the fly, and ensure persistence of data in messages. We demonstrate the technique on a multiplayer online game, written in SQL, with players who connect to a mobile ad hoc network through their portable devices. The overlay is defined by a combination of an ad hoc routing protocol, DSDV, together with a DHT. The application runs on the QuestMonitor platform, which allows to monitor the communication between peers, the evolution of the local data stores, as well as the execution of the declarative code.Nous proposons une approche basée sur les réseaux pair à pair pour distribuer de manière transparente des applications définies par des requêtes sur une base de données centralisée. Nous considérons des applications pour lesquelles les utilisateurs ont accès à des vues qui contiennent des fragments horizontaux des données qui les intéressent. Les réseaux logiques sont définis par des programmes déclaratifs simples dans le langage Netlog. La communication repose sur l'usage d'adresses implicites, qui peuvent être évaluées à la volée, et garantissent la persistance des données dans les messages. Nous montrons le fonctionnement du système pour un jeu en ligne multijoueur, joué par des joueurs qui utilisent leurs terminaux portables connectés à un réseau mobile ad hoc. Le réseau logique repose sur un protocole de routage pour réseau ad hoc, DSDV, couplé à une DHT. L'application tourne sur la platforme QuestMonitor, qui permet de contrôler la communication entre pairs, l'évolution des données locales, ainsi que l'exécution du code déclaratif

Messages with Implicit Destinations as Mobile Agents

International audienceApplications running over decentralized systems, distribute their computation on nodes/agents, which exchange data and services through messages. In many cases, the provenance of the data or service is not relevant, and applications can be optimized by choosing the most efficient solution to obtain them. We introduce a frameworkwhich allows messages with intensional destination, which can be seen as restricted mobile agents, specifying the desired service but not the exact node that carries it, leaving to the system the task of evaluating the extensional destination, that is an explicit address for that service. The intensional destinations are defined using queries that are evaluated by other agents while routing. We introduce the Questlog language, which allows to reformulate queries, and express complex strategies to pull distributed data. In addition, intensional addresses offer persistency to dynamic systems with nodes/agents leaving the system. We demonstrate the approach with examples taken from sensor networks, and show some experimental results on the QuestMonitor platform

Adaptive atomic capture of multiple molecules

International audienceFacing the scale, heterogeneity and dynamics of the global computing platform emerging on top of the Internet, autonomic computing has been raised recently as one of the top challenges of computer science research. Such a paradigm calls for alternative programming abstractions, able to express autonomic behaviours. In this quest, nature-inspired analogies regained a lot of interest. More specifically, the chemical programming paradigm, which envisions a program's execution as a succession of reactions between molecules representing data to produce a result, has been shown to provide some adequate abstractions for the high-level specification of autonomic systems.However, conceiving a runtime able to run such a model over large-scale platforms raises several problems, hindering this paradigm to be actually leveraged. Among them, the atomic capture of multiple molecules participating in concurrent reactions is one of the most significant.In this paper, we propose a protocol for the atomic capture of these molecules distributed and evolving over a large-scale platform. As the density of potential reactions has a significant impact on the liveness and efficiency of such a capture, the protocol proposed is made up of two sub-protocols, each of them aimed at addressing different levels of densities of potential reactions in the solution. While the decision to choose one or the other is local to each node participating in a program's execution, a global coherent behaviour is obtained. We also give an overview of the course of execution when a program contains multiple rules and provide a rule-changing mechanism. The proof of correctness, as well as intensive simulation results showing the efficiency and limited overhead of the protocol are given

Gestion des données distribuées avec le langage de règles Webdamlog

Notre but est de permettre à un utilisateur du Web d organiser la gestionde ses données distribuées en place, c est à dire sans l obliger à centraliserses données chez un unique hôte. Par conséquent, notre système diffèrede Facebook et des autres systèmes centralisés, et propose une alternativepermettant aux utilisateurs de lancer leurs propres pairs sur leurs machinesgérant localement leurs données personnelles et collaborant éventuellementavec des services Web externes.Dans ma thèse, je présente Webdamlog, un langage dérivé de datalogpour la gestion de données et de connaissances distribuées. Le langage étenddatalog de plusieurs manières, principalement avec une nouvelle propriété ladélégation, autorisant les pairs à échanger non seulement des faits (les données)mais aussi des règles (la connaissance). J ai ensuite mené une étude utilisateurpour démontrer l utilisation du langage. Enfin je décris le moteur d évaluationde Webdamlog qui étend un moteur d évaluation de datalog distribué nomméBud, en ajoutant le support de la délégation et d autres innovations tellesque la possibilité d avoir des variables pour les noms de pairs et des relations.J aborde de nouvelles techniques d optimisation, notamment basées sur laprovenance des faits et des règles. Je présente des expérimentations quidémontrent que le coût du support des nouvelles propriétés de Webdamlogreste raisonnable même pour de gros volumes de données. Finalement, jeprésente l implémentation d un pair Webdamlog qui fournit l environnementpour le moteur. En particulier, certains adaptateurs permettant aux pairsWebdamlog d échanger des données avec d autres pairs sur Internet. Pourillustrer l utilisation de ces pairs, j ai implémenté une application de partagede photos dans un réseau social en Webdamlog.Our goal is to enable aWeb user to easily specify distributed data managementtasks in place, i.e. without centralizing the data to a single provider. Oursystem is therefore not a replacement for Facebook, or any centralized system,but an alternative that allows users to launch their own peers on their machinesprocessing their own local personal data, and possibly collaborating with Webservices.We introduce Webdamlog, a datalog-style language for managing distributeddata and knowledge. The language extends datalog in a numberof ways, notably with a novel feature, namely delegation, allowing peersto exchange not only facts but also rules. We present a user study thatdemonstrates the usability of the language. We describe a Webdamlog enginethat extends a distributed datalog engine, namely Bud, with the supportof delegation and of a number of other novelties of Webdamlog such as thepossibility to have variables denoting peers or relations. We mention noveloptimization techniques, notably one based on the provenance of facts andrules. We exhibit experiments that demonstrate that the rich features ofWebdamlog can be supported at reasonable cost and that the engine scales tolarge volumes of data. Finally, we discuss the implementation of a Webdamlogpeer system that provides an environment for the engine. In particular, a peersupports wrappers to exchange Webdamlog data with non-Webdamlog peers.We illustrate these peers by presenting a picture management applicationthat we used for demonstration purposes.PARIS11-SCD-Bib. électronique (914719901) / SudocSudocFranceF