In this paper, the authors introduce and describe the concept of File System as a Services (FSaaS), an highly configurable cloud service that enables cooperating, distributed applications to define... Show More

In this paper, the authors introduce and describe the concept of File System as a Services (FSaaS), an highly configurable cloud service that enables cooperating, distributed applications to define their own rules and policies for managing sets of files shared. The FSaaS aims to create a logical virtual space, containing references to shared files, whose management layer supports the same functionalities of a file system (basic file operations) but where each single file can have different policies for consistency, synchronization and replication. This work explains the idea at the base of FSaaS, describes in details its main components and their interactions and illustrates two use cases for better explaining the provided functionalities.

Cloud computing environments provide flexible infrastructures for third-party management of organizations’ information technology (IT) assets. With web services being a standard for realizing... Show More

Cloud computing environments provide flexible infrastructures for third-party management of organizations’ information technology (IT) assets. With web services being a standard for realizing web-based business capabilities, the emergence of cloud computing will bring new challenges to different web service activities. In this paper, the authors propose an agent-based framework that employs a team of management and monitoring agents on different scopes to provides effective service management in a cloud environment. To tackle the dynamism in service operations, an adaptive monitoring algorithm is proposed. The algorithm is inspired by the congestion control approach from the TCP protocol and provides efficient, up-to-date information about service status without exhaustive monitoring. Experimental results show that the monitoring algorithm provides significant benefits when compared to the more exhaustive methods. This approach also facilitates other service activities, such as cross cloud service discovery.

This paper introduces a web-based semantic tool that provides more detailed information about a term selected by the user of a web browser, the Clinical Eye. This tool was initially designed for the... Show More

This paper introduces a web-based semantic tool that provides more detailed information about a term selected by the user of a web browser, the Clinical Eye. This tool was initially designed for the medical area of cardiology, which is still controversial in terms of vocabularies. Anontology has been developed as a reference base where those different vocabularies converge. The information supplied by the tool was taken from specialized medical web pages and technical documents. It is a tool of low interference for ongoing activities, so it can be used during a clinical activity. It has been designed according to requirements raised by studies in various medical communities, which pointed the use of Internet during consultations and medical needs for deep information.

A web service composition is considered as a real revolution in SOA (Service Oriented Architecture). It is based on assembling independent and loosely coupled services to build a composed web... Show More

A web service composition is considered as a real revolution in SOA (Service Oriented Architecture). It is based on assembling independent and loosely coupled services to build a composed web service. This composition can be described from both a local or a global perspective by respective orchestration or choreography. The validation of web service orchestrations is the main topic of this work. It is based on the verification of two classes of properties: generic and specific properties. The former can be checked for any invoked web services whereas the specific properties are different interdependence relationships between activities within an orchestration process. These properties cannot be directly verified on the orchestration process, so, the authors have to use formal techniques. In this paper, they propose a formal approach for the validation of web service orchestrations. This work adopts WS-BPEL 2.0 as the language to describe the web service orchestration and uses the SPIN model-checker for the verification engine. The WS-BPEL specification is translated into Promela code which is the input language for the SPIN model-checker, in order to check generic and specific properties expressed with LTL (Linear Temporal Logic).

Managing dynamic reconfiguration of software systems is a tedious task in the software development because of the substantially increasing need for continuously available systems even at runtime. In... Show More

Managing dynamic reconfiguration of software systems is a tedious task in the software development because of the substantially increasing need for continuously available systems even at runtime. In particular, the software architecture of dynamically adaptive systems must continuously adapt to varying environmental conditions and user requirements. Therefore, they propose a wide range of possible configurations. The static enumeration of all the possible configurations is a difficult task. Moreover, not all dynamic reconfiguration operations can be foreseen at design time. Some reconfigurations may appear when the system is already deployed. In this context, we propose to combine the Architecture Description Languages and the Aspect-Oriented Software Development paradigm in order to make the dynamic reconfiguration process easier to design, understand and possible to validate. Also, this combination allows to easily evolving the reconfiguration policies even at runtime.