Survey: Agent-based Middlewares for Context Awareness

In the last few years, many middlewares for context awareness have claimed to be agent-based. In this paper, we make a survey on the most known frameworks. We classify them according to their level of conformity to the agent paradigm and we discuss the usefulness of agents in these frameworks. Based on this survey, we enumerate several advantages of using agents in context-aware middlewares and give illustrative examples. We also point to the weakness of existing frameworks and identify challenges to be addressed

La géosimulation orientée agent : un support pour la planification dans le monde réel

La planification devient complexe quand il s’agit de gérer des situations incertaines. Prédire de façon précise est une tâche fastidieuse pour les planificateurs humains. L’approche Simulation-Based Planning consiste à associer la planification à la simulation. Chaque plan généré est simulé afin d’être testé et évalué. Le plan le plus approprié est alors retenu. Cependant, le problème est encore plus complexe lorsque viennent s’ajouter des contraintes spatiales. Par exemple, lors d’un feu de forêt, des bulldozers doivent construire une ligne d’arrêt pour arrêter la propagation des feux. Ils doivent alors tenir compte non seulement de l’avancée des feux mais aussi des caractéristiques du terrain afin de pouvoir avancer plus facilement. Nous proposons une approche de géosimulation basée sur les agents et qui a pour but d’assister la planification dans un espace réel, à large échelle géographique et surtout à forte composante spatiale. Un feu de forêt est un problème typique nécessitant une planification dans un monde réel incertain et soumis à de fortes contraintes spatiales. Nous illustrons donc notre approche (nommée ENCASMA) sur le problème des feux de forêts. L’approche consiste à établir un parallélisme entre l’Environnement Réel ER (p.ex. une forêt incendiée) et un Environnement de Simulation ES (p.ex. une reproduction virtuelle de la forêt incendiée). Pour garantir un niveau acceptable de réalisme, les données spatiales utilisées dans l’ES doivent absolument provenir d’un SIG (Système d’information Géographique). Les planificateurs réels comme les pompiers ou les bulldozers sont simulés par des agents logiciels qui raisonnent sur l’espace modélisé par l’ES. Pour une meilleure sensibilité spatiale (pour tenir compte de toutes les contraintes du terrain), les agents logiciels sont dotés de capacités avancées telles que la perception. En utilisant une approche par géosimulation multiagent, nous pouvons générer une simulation réaliste du plan à exécuter. Les décideurs humains peuvent visualiser les conséquences probables de l’exécution de ce plan. Ils peuvent ainsi évaluer le plan et éventuellement l’ajuster avant son exécution effective (sur le terrain). Quand le plan est en cours d’exécution, et afin de garantir la cohérence des données entre l’ER et l’ES, nous gardons trace sur l’ES des positions (sur l’ER) des planificateurs réels (en utilisant les technologies du positionnement géoréférencé). Nous relançons la planification du reste du plan à partir de la position courante de planificateur réel, et ce de façon périodique. Ceci est fait dans le but d’anticiper tout problème qui pourrait survenir à cause de l’aspect dynamique de l’ER. Nous améliorons ainsi le processus classique de l’approche DCP (Distributed Continual Planning). Enfin, les agents de l’ES doivent replanifier aussitôt qu’un événement imprévu est rapporté. Étant donné que les plans générés dans le cas étudié (feux de forêts) sont essentiellement des chemins, nous proposons également une approche basée sur la géosimulation orientée agent pour résoudre des problèmes particuliers de Pathfinding (recherche de chemin). De plus, notre approche souligne les avantages qu’apporte la géosimulation orientée agent à la collaboration entre agents humains et agents logiciels. Plus précisément, elle démontre : • Comment la cognition spatiale des agents logiciels sensibles à l’espace peut être complémentaire avec la cognition spatiale des planificateurs humains. • Comment la géosimulation orientée agent peut complémenter les capacités humaines de planification lors de la résolution de problèmes complexes. Finalement, pour appliquer notre approche au cas des feux de forêts, nous avons utilisé MAGS comme plate-forme de géosimulation et Prometheus comme simulateur du feu. Les principales contributions de cette thèse sont : 1. Une architecture (ENCASMA) originale pour la conception et l’implémentation d’applications (typiquement des applications de lutte contre les désastres naturels) dans un espace géographique réel à grande échelle et dynamique. 2. Une approche basée sur les agents logiciels pour des problèmes de Pathfinding (recherche de chemin) particuliers (dans un environnement réel et à forte composante spatiale, soumis à des contraintes qualitatives). 3. Une amélioration de l’approche de planification DCP (plus particulièrement le processus de continuité) afin de remédier à certaines limites de la DCP classique. 4. Une solution pratique pour un problème réel et complexe : la lutte contre les feux de forêts. Cette nouvelle solution permet aux experts du domaine de mieux planifier d’avance les actions de lutte et aussi de surveiller l’exécution du plan en temps réel.Planning becomes complex when addressing uncertain situations. Accurate predictions remain a hard task for human planners. The Simulation-Based Planning approach consists in associating planning and simulation. Each generated plan is simulated in order to be tested and evaluated. The most appropriate plan is kept. The problem is even more complex when considering spatial constraints. For example, when fighting a wildfire, dozers build a firebreak to stop fire propagation. They have to take into account not only the fire spread but also the terrain characteristics in order to move easily. We propose an agent-based geosimulation approach to assist such planners with planning under strong spatial constraints in a real large-scale space. Forest fire fighting is a typical problem involving planning within an uncertain real world under strong spatial constraints. We use this case to illustrate our approach (ENCASM). The approach consists in drawing a parallel between the Real Environment RE (i.e. a forest in fire) and the Simulated Environment SE (i.e. a virtual reproduction of the forest). Spatial data within the SE should absolutely come from a GIS (Geographic Information System) for more realism. Real planners such as firefighters or dozers are simulated using software agents which reason about the space of the SE. To achieve a sufficient spatial awareness (taking into account all terrain’s features), agents have advanced capabilities such as perception. Using a multiagent geosimulation approach, we can generate a realistic simulation of the plan so that human decision makers can visualize the probable consequences of its execution. They can thus evaluate the plan and adjust it before it can effectively be executed. When the plan is in progress and in order to maintain coherence between RE and SE, we keep track in the SE of the real planners’ positions in the RE (using georeferencing technologies). We periodically replan the rest of the plan starting from the current position of the real planner. This is done in order to anticipate any problem which could occur due to the dynamism of the RE. We thus enhance the process of the classical Distributed Continual Planning DCP. Finally, the agents must replan as soon as an unexpected event is reported by planners within the RE. Since plans in the studied case (forest fires) are mainly paths, we propose a new approach based on agent geosimulation to solve particular Pathfinding problems. Besides, our approach highlights the benefits of the agent-based geo-simulation to the collaboration of both humans and agents. It thus shows: • How spatial cognitions of both spatially aware agents and human planners can be complementary. • How agent-based geo-simulation can complement human planning skills when addressing complex problems. Finally, when applying our approach on firefighting, we use MAGS as a simulation platform and Prometheus as a fire simulator. The main contributions of this thesis are: 1. An original architecture (ENCASMA) for the design and the implementation of applications (typically, natural disasters applications) in real, dynamic and large-scale geographic spaces. 2. An agent-based approach for particular Pathfinding problems (within real and spatially constrained environments and under qualitative constraints). 3. An enhancement of the DCP (particularly, the continual process) approach in order to overcome some limits of the classical DCP. 4. A practical solution for a real and complex problem: wildfires fighting. This new solution aims to assist experts when planning firefighting actions and monitoring the execution of these plans

Enabling Cyber Physical Systems with Wireless Sensor Networking Technologies, Multiagent System Paradigm, and Natural Ecosystems

Wireless sensor networks (WSNs) are key components in the emergent cyber physical systems (CPSs). They may include hundreds of spatially distributed sensors which interact to solve complex tasks going beyond their individual capabilities. Due to the limited capabilities of sensors, sensor actions cannot meet CPS requirements while controlling and coordinating the operations of physical and engineered systems. To overcome these constraints, we explore the ecosystem metaphor for WSNs with the aim of taking advantage of the efficient adaptation behavior and communication mechanisms of living organisms. By mapping these organisms onto sensors and ecosystems onto WSNs, we highlight shortcomings that prevent WSNs from delivering the capabilities of ecosystems at several levels, including structure, topology, goals, communications, and functions. We then propose an agent-based architecture that migrates complex processing tasks outside the physical sensor network while incorporating missing characteristics of autonomy, intelligence, and context awareness to the WSN. Unlike existing works, we use software agents to map WSNs to natural ecosystems and enhance WSN capabilities to take advantage of bioinspired algorithms. We extend our architecture and propose a new intelligent CPS framework where several control levels are embedded in the physical system, thereby allowing agents to support WSNs technologies in enabling CPSs

Privacy-aware web services in smart homes

Smart homes can assist their inhabitants with mental and physical tasks, and monitor their safety and health. However, the systems that empower such homes use sensitive information that could be misused by external systems resulting in violations of the inhabitants\u27 privacy. In this paper, we introduce a Web services-centric solution to handle privacy concerns. Web services provide the functionalities that allow users remotely interact with the systems empowering the smart homes. In addition the solution uses policies to control how Web services handle privacy concerns and penalize those Web services that do not bind to these policies. Moreover the solution uses trust and reputation to select the most trustworthy Web services. © 2009 Springer Berlin Heidelberg

On the reputation of communities of web services

Web services communities are virtual clusters that agglomerate Web services with the same functionality. However, selecting the best community to deal with is challenging to both users and providers. Reputation has been widely used for evaluating and ranking candidates. In this paper, we introduce a reputation-based Web services community architecture and define some of the performance metrics that are needed to assess the reputation of a Web service community as perceived by the users and providers. Copyright 2008 ACM

Contribution to the problem of semantic security of systems : model-based engineering approach

Les infrastructures industrielles critiques seront dotées de plusieurs équipements embarqués intelligents. Elles exploitent des systèmes complexes, embarqués, intelligents et sémantiques pour leurs fonctionnements, en local et à distance, dans un contexte de développement, de villes intelligentes et du web des objets. Elles emploient, de plus en plus de systèmes «contrôle/commande», pour la surveillance des plateformes industrielles critiques, en temps réel. Les infrastructures critiques seront de plus en plus communicantes dans le cadre des échanges des alarmes et la mise en place de marchés euro-méditerranéens de l’électricité et davantage plus vulnérables. La cybernétique des plateformes critiques se développe, de jour en jour, essentiellement avec l’usage de systèmes complexes embarqués intelligents sémantiques, des services web, des ontologies,..etc. Ils sont tous embarqués sur les instruments intelligents, composant les systèmes sémantiques. Des réseaux de télécommunication intelligents, filaire et sans fil, dit hybrides, se développent. Ils représentent un grand challenge, pour la sécurité des systèmes communicants futurs. Dans un contexte de développement du web, des objets et des villes intelligentes, nos travaux de recherche visent à renforcer les bases de la sécurité et de la cybernétique sémantique, pour les systèmes communicants. Dans notre solution globale, en matière de sécurité sémantique, des infrastructures critiques, nous avons proposé plusieurs sous-solutions, tels que des méta-modèles et des modèles, ainsi qu’une stratégie de sécurité de bout en bout, avec un fonctionnement sur un réseau Cloud global, hybride et sécuriséCritical, modern, current, and even future industrial infrastructures will be equipped with several intelligent embedded equipment. They exploit complex, embedded, intelligent and semantic systems for their operations, locally and remotely, in a context of development, smart cities and the web of things. They are using more and more SCADA and DCS control systems to monitor critical industrial platforms in real time. Critical infrastructures will be more and more communicating in the framework of the exchanges of allarmes and the establishment of Euro-Mediterranean markets of the életcricité and also more and more vulnerable, to classic and even semantic attacks, to viruses, to Trojan horses. The cybernetics of critical platforms is growing, day by day, mainly with the use of complex embedded intelligent semantic systems, web services, ontologies, and format files (XML, OWL, RDF, etc.). They are all embedded in intelligent instruments, making up semantic SCADA systems. Intelligent telecommunication networks, wired and wireless, called hybrids, are developing. They represent a great challenge for the security of future communicating systems. In a context of development of the web of things and smart cities, our research aims to strengthen the bases of security and semantic cybernetics, for communicating systems. In our global solution for semantic security, critical infrastructures, we have proposed several sub-solutions, such as metamodels and models, as well as an end-to-end security strategy, with operation on a global cloud network, hybrid and secure

Agent-Based Approach for Connected Vehicles and Smart Road Signs Collaboration

Road traffic is drastically increasing in big cities around the world. In order to enable a flexible management of this traffic, Intelligent Transportation System (ITS) solutions are relying on emergent ubiquitous, mobile, and communication technologies, particularly to intelligently deal with the limited capacities of the existing road infrastructures. While intelligence is left to the autonomous and connected vehicles as well as to the ITS, the road infrastructure has been mostly playing a passive role (as a source of data). Road signage, in particular, are in best cases dynamic but do not play an active role in monitoring traffic and incidents. We propose in this paper to build Smart Road Signs (SRS) that can collaborate with Connected Vehicles in order to monitor traffic and warn drivers about any incident or danger. Our SRSs are meant to operate autonomously in order to detect road traffic problems, share appropriate information with vehicles in the vicinity, and display relevant messages based on the ongoing contextual situation. To meet our goals, we rely on Multi-Agent Systems to design SRSs as proactive components in the ITS landscape. We also rely on agent mobility in order to strengthen the collaboration with the connected vehicles

Agent-based Geo-simulation to Support Human Planning and Spatial Cognition

Abstract. In this paper we emphasize the strengths and weaknesses of human planning and especially within a geographic space. We propose a multi-agent simulation approach in order to overcome some of these limitations while reasoning about a large-scale geographic space. A cognitive complementarity between software agents and human beings emerges from this approach. An illustration on wildfire fighting is also presented