OrchestrationdeWebServices Fiables

Abstract

ABSTRACT : Service Oriented Computing (SOC) represents a paradigm for building distributed applications over the Internet. Service Oriented Architecture (SOA) is an architectural style that allows developing these applications based on services. Over the past decade, Web services orchestration has become thriving area of research and academic efforts. Although many orchestration-related challenges have been tackled, orchestration reliability and its verification are still an open, critical and prerequisite issue as web service orchestration are affecting several life-days activities. This thesis addresses the subject of reliable web service orchestrations. In particular, it contributes a set of approaches, techniques and tools to address the selection and orchestration of reliable web services. Firstly, it refines life-cycle phases of service orchestration to ensure reliability analysis and verification during orchestration design and run-time. As well as it proposes an architecture, based on an enhanced service registry, to achieve the same goal. Secondly, it introduces an approach for measuring web services similarity based on their interfaces that serves as a basic technique for identifying similarity, substitutability and composability relationships between web services. Besides, a Tool coined WSSIM, implementing this approach is developed, and it is available for reproducible research. The tool is experimented on a set real web services for validation. Thirdly, the thesis contributes with an approach for the identification of simple and complex service substitutes. The latter is built up on similarity measurement, FCA classification and reliability analysis. In addition, a set of algorithms are presented to describe the functionality of different phases in the identification process. Fourthly, to consider reputation of services as a ’softer’ form or reliability, the thesis introduces a framework and a mathematical model for web service reputation management.