Efficient Context-aware Service Discovery in Multi-Protocol Pervasive Environments

International audienceService discovery is a critical functionality of emerging pervasive computing environments. In such environments, service discovery mechanisms need to (i) overcome the heterogeneity of hardware devices, software platforms, and networking infrastructures; and (ii) provide users with an accurate selection of services that meet their current requirements. To address these issues, we have developed the Multi- Protocol Service Discovery and Access (MSDA) middleware platform2, which provides context-aware service discovery and access in pervasive environments. This paper primarily focuses on the design and implementation of the context-awareness support of MSDA. Context-awareness not only provides a more accurate service selection, but also enables a more efficient dissemination of service requests across heterogeneous pervasive environments. We present the design and prototype implementation of MSDA, along with experimental results that demonstrate the advantages derived by introducing context awareness

Interoperability of Service Discovery Protocols: Transparent versus Explicit Approaches

International audienceDiscovering networked services in pervasive computing environments is problematic as multiple Service Discovery Protocols (SDPs), differing on their services description formats as well as advertisement and request models, have already become (de-facto) standards. This calls for a solution to SDP interoperability, enabling clients to locate networked services independent of the SDP they use to advertise their presence. In this paper, we report on our experience in developing two such solutions: the transparent approach of INDISS based on message translation, and the explicit approach of MSDA based on protocol integration. While efficient and able to support legacy clients and services, INDISS is limited by the basic service information available in existing SDPs, and assumptions about the network protocols used by the SDPs. Advanced discovery features required by pervasive environments, such as context or security management, can only be provided by more complex discovery frameworks like MSDA, but come at a price

Interoperable Semantic & Syntactic Service Matching for Ambient Computing Environments

International audienceThe inherent heterogeneity of ambient computing environments and their constant evolution requires middleware platforms to manage networked components designed, developed and deployed independently. Such management must also be efficient to cater for resource-constrained devices and highly dynamic situations due to the spontaneous appearance and disappearance of networked resources. For service discovery protocols (SDP), one of the main functions of service-oriented architectures (SOA), the efficiency of the matching of syntactic service descriptions is most often opposed to the fullness of the semantic approach. As part of the PLASTIC middleware for ambient computing environments, we present in this paper an interoperable service matching and ranking platform, which is able to process service descriptions from both semantic and syntactic service description languages. To that end, we define a generic, modular description language able to record service functional properties, potentially extended with semantic annotations. An evaluation of the prototype implementation of our platform demonstrates that multi-protocols service matching supporting various levels of expressiveness can be achieved in ambient computing environments

ubiSOAP: A Service Oriented Middleware for Ubiquitous Networking

International audienceThe computing and networking capacities of today's wireless portable devices allow for ubiquitous services, which are seamlessly networked. Indeed, wireless handheld devices now embed the necessary resources to act as both service clients and providers. However, the ubiquitous networking of services remains challenged by the inherent mobility and resource constraints of the devices, which make services a priori highly volatile. This paper discusses the design, implementation and experimentation of the ubiSOAP service-oriented middleware, which leverages wireless networking capacities to effectively enable the ubiquitous networking of services. ubiSOAP specifically defines a layered communication middleware that underlies standard SOAP-based middleware, hence supporting legacy Web Services while exploiting nowadays ubiquitous connectivity

Uma infraestrutura para integração entre dispositivos computacionais heterogêneos baseada na especificação DPWS

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da ComputaçãoServiços computacionais têm proporcionado facilidades à vida das pessoas, provendo mais agilidade em operações e acesso a informação. Muitos desses serviços são providos por dispositivos que estão espalhados no ambiente de convívio comum. Alguns destes equipamentos podem se conectar e trocar dados entre si utilizando uma infra-estrutura de rede. Entretanto, um conjunto maior de serviços poderia ser oferecido se dispositivos que empregam diferentes tecnologias de comunicação também pudessem se conectar e trocar dados. Dessa forma, seria possível aproveitar classes diversas de equipamentos para construção de soluções que atendam cenários de aplicação diversos. Com o objetivo de proporcionar um mecanismo que reúna serviços oferecidos por dispositivos heterogêneos é proposto neste trabalho o Device Service Bus (DSB). O DSB consiste em uma infra-estrutura de middleware empregada para integração de diferentes dispositivos embarcados em ambiente de computação ubíqua. Baseado no Devices Profile for Web Services (DPWS) como tecnologia de integração, o DSB permite interação de vários dispositivos que adotam diferentes padrões de comunicação. Esse trabalho apresenta uma implementação de um protótipo do DSB, que provê componentes de software que são implantados em dispositivos responsáveis por construir um barramento de integração entre dispositivos heterogêneos. Além disso, dois cenários de aplicação real reunindo sensores Sun SPOT e leitores RFID, e medições de desempenho obtidas com estes dispositivos também são apresentados nesse trabalho

Initial CONNECT Architecture

Interoperability remains a fundamental challenge when connecting heterogeneous systems which encounter and spontaneously communicate with one another in pervasive computing environments. This challenge is exasperated by the highly heterogeneous technologies employed by each of the interacting parties, i.e., in terms of hardware, operating system, middleware protocols, and application protocols. The key aim of the CONNECT project is to drop this heterogeneity barrier and achieve universal interoperability. Here we report on the development of the overall CONNECT architecture that will underpin this solution; in this respect, we present the following contributions: i) an elicitation of interoperability requirements from a set of pervasive computing scenarios, ii) a survey of existing solutions to interoperability, iii) an initial view of the CONNECT architecture, and iv) a series of experiments to provide initial validation of the architecture

Intermediate CONNECT Architecture

Interoperability remains a fundamental challenge when connecting heterogeneous systems which encounter and spontaneously communicate with one another in pervasive computing environments. This challenge is exasperated by the highly heterogeneous technologies employed by each of the interacting parties, i.e., in terms of hardware, operating system, middleware protocols, and application protocols. The key aim of the CONNECT project is to drop this heterogeneity barrier and achieve universal interoperability. Here we report on the activities of WP1 into developing the CONNECT architecture that will underpin this solution. In this respect, we present the following key contributions from the second year. Firstly, the intermediary CONNECT architecture that presents a more concrete view of the technologies and principles employed to enable interoperability between heterogeneous networked systems. Secondly, the design and implementation of the discovery enabler with emphasis on the approaches taken to match compatible networked systems. Thirdly, the realisation of CONNECTors that can be deployed in the environment; we provide domain specific language solutions to generate and translate between middleware protocols. Fourthly, we highlight the role of ontologies within CONNECT and demonstrate how ontologies crosscut all functionality within the CONNECT architecture

Hybrid approaches based on computational intelligence and semantic web for distributed situation and context awareness

2011 - 2012The research work focuses on Situation Awareness and Context Awareness topics. Specifically, Situation Awareness involves being aware of what is happening in the vicinity to understand how information, events, and one’s own actions will impact goals and objectives, both immediately and in the near future. Thus, Situation Awareness is especially important in application domains where the information flow can be quite high and poor decisions making may lead to serious consequences. On the other hand Context Awareness is considered a process to support user applications to adapt interfaces, tailor the set of application-relevant data, increase the precision of information retrieval, discover services, make the user interaction implicit, or build smart environments. Despite being slightly different, Situation and Context Awareness involve common problems such as: the lack of a support for the acquisition and aggregation of dynamic environmental information from the field (i.e. sensors, cameras, etc.); the lack of formal approaches to knowledge representation (i.e. contexts, concepts, relations, situations, etc.) and processing (reasoning, classification, retrieval, discovery, etc.); the lack of automated and distributed systems, with considerable computing power, to support the reasoning on a huge quantity of knowledge, extracted by sensor data. So, the thesis researches new approaches for distributed Context and Situation Awareness and proposes to apply them in order to achieve some related research objectives such as knowledge representation, semantic reasoning, pattern recognition and information retrieval. The research work starts from the study and analysis of state of art in terms of techniques, technologies, tools and systems to support Context/Situation Awareness. The main aim is to develop a new contribution in this field by integrating techniques deriving from the fields of Semantic Web, Soft Computing and Computational Intelligence. From an architectural point of view, several frameworks are going to be defined according to the multi-agent paradigm. Furthermore, some preliminary experimental results have been obtained in some application domains such as Airport Security, Traffic Management, Smart Grids and Healthcare. Finally, future challenges is going to the following directions: Semantic Modeling of Fuzzy Control, Temporal Issues, Automatically Ontology Elicitation, Extension to other Application Domains and More Experiments. [edited by author]XI n.s