Stéphanie Chollet

Lessons learned in building pervasive platforms

The purpose of pervasive applications is to be invisible and to require a minimal amount of user attention. But invisibility raises lots of hard challenges, blocking the long-awaited pervasive era to emerge. The device heterogeneity and volatility, security enforcement and context-awareness are just some of the issues a developer must tackle inside the application code. To industrialize such development, we propose to use an application server dedicated to the pervasive environment. Thanks to this server, developers focus on the application, delegating to the server most of the pervasive constraint management. However, providing such a platform is a very difficult task. The pervasive environment constraints must be handled by this server in a consistent way, while being flexible enough to support the different applications. This paper describes the requirements of the pervasive applications and how our platform, named iCASA, deals with them.

An Extensible Abstract Service Orchestration Framework

Service composition is complex. It has to reach a set of pre-defined non-functional qualities, like security for instance, which requires the production of complicated code.This code, often distributed between client and server sides, is highly error-prone and difficult to maintain. In this paper, we present a generative environment for the orchestration of abstract services and the separate specification of non-functional properties. This environment has been built within the European SODA project and validated on several industrial use cases. In this paper, we focus on an alarm management scenario with stringent security requirements.

Security Specification at Process Level

In this paper, we present a process-oriented tool allowing the specification of security properties at the service composition level. The tool is based on the notions of abstract and concrete services as well as on the concept of separation of concerns. It provides a framework that allows different people to effectively discuss security issues. Abstract services can be viewed as activities rather than as technical services and are such better understood by non-technical people. Similarly, security is discussed in terms of needs and no complex security technologies are to be specified. The tool relies between these two meta-models specifying orchestration-related concepts and security concepts. Meta-links between the meta-models have been defined to specify the authorized security constraints on the orchestrated services. The tool has been validated on an application specified by Thales.

Development Tool for Service-Oriented Applications in Smart Homes

In this paper, we present a model-driven, domain-centric tool allowing the specification of service-oriented applications through abstract services composition. Executable applications, made of concrete services, are automatically generated and deployed. This tool can be customized with domain-specific knowledge. Our contributions in this paper are to slightly extend the tool to be used in the demanding home computing domain. An approach for modelling and implementing dynamic service composition is provided for satisfying the dynamic home environment. This work has been carried out in collaboration with Schneider Electric.

Practical use of formal concept analysis in service-oriented computing

Pervasive applications are encountered in a number of settings, including smart houses, intelligent buildings or connected plants. Service-Oriented Computing is today the technology of choice for implementing and exposing resources in such environments. The selection of appropriate services at the right moment in order to compose meaningful applications is however a real issue. In this paper, we propose a FCA-based solution to this problem. We have integrated FCA algorithms in our pervasive gateways and adapted them in order to allow efficient runtime selection of heterogeneous and dynamic services. This work has been applied to realistic use cases in the scope of a European project.

Heterogeneous Service Selection Based on Formal Concept Analysis

In this paper, we propose an approach based on Formal Concept Analysis in order to organize the services registry at runtime and to allow the ”best” service selection among heterogeneous and secured services according to a set of specifications. This solution has been validated in the European SODA project on pervasive applications.

Service-based architecture and frameworks for pervasive health applications

Healthcare costs are booming as population ages and need healthcare. Pervasive applications are expected to take healthcare into peoples homes and thus cut health-related costs. However, the lack of appropriate middleware to collect and integrate pervasive data is a brake to their development. In this paper, we present the integration of iCasa and Cilia, two service-oriented frameworks, and show it can be applied to medical applications. These frameworks facilitate the work of developers and exhibit autonomic features easing administration.

Transparently Adding Security Properties to Service Orchestration

In this paper, we present a tool allowing the design of service orchestration at a high level of abstraction. This tool also allows specifying security properties, also in an abstract way, as annotations on the services orchestration. Our purpose is to generate code, including security code, from this specification. This is especially important in the context of complex execution platforms like enterprise service buses. Our tool is used in the context of industrial plants using more and more services like DPWS to implement applications.

A model-based approach to context management in pervasive platforms

Pervasive computing envisions environments where computers are blended into everyday objects in order to provide added-value services to people. This new form of computing gives rise to huge economical and societal expectations. However, pervasive applications raise major challenges in term of software engineering and remain hard to develop, deploy, execute and maintain. Context-awareness, in particular, is a salient and difficult property that must be met by pervasive applications. In this paper, we propose a service-oriented framework facilitating the design and execution of a context management module in pervasive platforms. Our approach is illustrated with a smart home example and implemented on top of iPOJO, the Service-Oriented Component Model of our pervasive platform iCasa.

fANFARE: Autonomic Framework for Service-Based Pervasive Environment

The ability to react quickly to unpredictable changes in the environment is a key requirement in pervasive computing. This paper presents fANFARE, a framework for the autonomic management of service-oriented applications in pervasive environments. Specifically, it focuses on the configuration and optimization of pervasive applications deployed on OSGi platforms. We propose to handle runtime administration through a hierarchy of autonomic managers, that is a platform manager and a number of application managers and dependency managers. Our approach has been implemented and validated on pervasive use cases within the MEDICAL project funded by the French Ministry of Industry.