Theses Riadh

Sujet : Une démarche de spécification, de conception et de développement pour les applications à base de services Web auto-adaptables

http://tel.archives-ouvertes.fr/tel-00401055/fr/

Financement: Bourse CMCU et bourse tunisienne du 4/10/2005 jusqu'à 31/12/2007 + CNRS de 01/01/2008 jusqu'à 30/06/2009

Etablissement: UPS

École doctorale: EDSYS

Directeur de thèse : Khalil Drira (Labo: LAAS-CNRS)

Etablissement de co-tutelle: ENIS

Directeur de thèse : Mohamed Jmaiel (Labo: REDCAD)

Résumé:

Nos travaux de recherche abordent la problématique de l'adaptabilité dans les applications orientées services et plus spécifiquement basées sur la technologie des Services Web. Nous nous intéressons à un contexte impliquant des applications logicielles construites par composition de services web distribués et multipropriétaires. Dans ce cadre, l'objectif principal est de fournir des mécanismes non intrusifs (i.e. par interception de messages SOAP) d'adaptation afin de fournir une qualité de service acceptable tout au long de l'exécution. Nous définissons pour cela une approche formelle et des dispositifs logiciels couvrant toute la boucle de la gestion d'adaptation allant du monitoring de la QoS jusqu'aux actions préventive de réparation. Nous avons réalisé un prototype comprenant ces différentes tâches. Chaque phase est traitée par un module implanté sous forme de service web. L'approche globale a été validée dans le cadre d'un cas d'étude pour le commerce électronique et des résultats expérimentaux ont été obtenus en utilisant la grille de calcul GRID5000.

Publications:

1. R.BEN HALIMA , K.GUENNOUN , K.DRIRA , M.JMAIEL

Providing predictive self-healing for web services: a QoS monitoring and analysis-based approach

Rapport LAAS No08620

Journal of Information Assurance and Security (JIAS), Vol.3, N°3, pp.175-184, Septembre 2008

Monitoring and analysis of QoS are crucial steps for the provisioning of self-healing web services and for managing web service-based distributed interactive applications. Dealing with these issues becomes even more challenging when applications are dynamically built by composition of distributed services involving different service providers. In this case, assuming access to the internal logic and its implementation within the composed web services is not realistic. In this paper, we propose an architectural framework for monitoring and analysis of QoS driven by models for QoS analysis. This framework has been implemented and experimented for the web service technology within the European WS-DIAMOND1 project. We consider the general context where only SOAP messages between web services are monitored. The main novelty of our approach is, on the one hand, to provide a generic application-independent framework. On the other hand, we provide models allowing QoS deficiencies to be detected and considered as an indicator of the health degradation of the monitored web services.

2. R.BEN HALIMA , K.DRIRA , M.JMAIEL

A QoS-oriented reconfigurable middleware for self-healing web services

Rapport LAAS No08352

IEEE International Conference on Web Services (ICWS 2008), Beijing (Chine), 23-26 Septembre 2008, pp.104-111

Maintaining the Quality of Service (QoS) is important for self-healing web service-based distributed interactive applications. It requires the ability to deal with permanently changing constraints both at the communication and the execution levels. Preventing or repairing QoS degradation also requires the capacity of identifying its possible or actual sources and the capacity of reconfiguration decision and enforcement. Dealing with these issues is especially challenging for web services since the self-healing solution has to preserve the dynamic composition property and to be seamless for the service requesters, while being always usable under the different deployment constraints. In this paper, we present a self-healing middleware framework able to provide the self-healing properties for QoS management in web service-based distributed interactive applications. The framework implementation has been achieved in the context of the WS-DIAMOND project. It covers the whole cycle of adaptation management including monitoring and analysis of QoS values, and substitution-based reconfiguration.

3. O.NABUCO DE ARAUJO , R.BEN HALIMA , K.DRIRA , M.G.FUGINI , S.MODAFFERI , E.MUSSI

Model-based Qos-enabled self-healing web services

Rapport LAAS No08324

1st International Workshop on Data Management in Virtual Engineeirng, Turin (Italie), 1-5 Septembre 2008, pp.711-715

Failures during web service execution may depend on a wide variety of causes, such as network faults, server crashes, or application-related errors, such asunavailability of a requested web service, errors in the orchestration of choreography of applications, missing data or parameters in an execution fow, or low Quality of Service (QoS). In this paper, we propose a healing architecture able to handle web service faults in a self-healing way, discussing infrastructural faults and web service and Web application faults. The self-healing architecture manages repair actions, such as substitution of a faulty service or duplication of overloaded services. Implemented prototypes involving QoS in coordinated web services are illustrated and discussed.

4. R.PEGORARO , R.BEN HALIMA , K.DRIRA , K.GUENNOUN , J.M.ROSARIO

A framework for monitoring and runtime recovery of web service-based applications

Rapport LAAS No08219

10th International Conference on Enterprise Information Systems (ICEIS 2008), Barcelone (Espagne), 12-16 Juin 2008, 6p.

Service provisioning is a challenging research area for the design and implementation of autonomic serviceoriented software systems. It includes automated QoS management for such systems and their applications. Monitoring, Diagnosis and Repair are three key features of QoS management. This work presents a selfhealing Web service-based framework that manages QoS degradation at runtime. Our approach is based on proxies. Proxies act on meta-level communications and extend the HTTP envelope of the exchanged messages with QoS-related parameter values. QoS Data are filtered over time and analysed using statistical functions and the Hidden Markov Model. Detected QoS degradations are handled with proxies. We experienced our framework using an orchestrated electronic shop application (FoodShop).

5. R.BEN HALIMA , K.GUENNOUN , K.DRIRA , M.JMAIEL

Non-intrusive QoS monitoring and analysis for self-healing web services

Rapport LAAS No08066

1st International Conference on the Applications of Digital Information and Web Technologies (ICADIWT 2008), Ostrava (République Tchèque), 4-6 Août 2008, pp.549-554

Monitoring and analysis of QoS are crucial steps for the provisioning of self-healing web services and for managing web service-based distributed interactive applications. Dealing with these issues becomes even more challenging when applications are dynamically built by composition of distributed services involving different service providers. In this case, assuming access to the internal logic and its implementation within the composed web services is not realistic. In this paper, we propose an architectural framework for monitoring and analysis of QoS driven by models for QoS analysis. This framework has been implemented and experimented for the web service technology within the European WS-DIAMOND project. We consider the general context where only SOAP messages between web services are monitored. The main novelty of our approach is, on the one hand, to provide a generic application-independent framework. On the other hand, we provide models allowing QoS deficiencies to be detected and considered as an indicator of the health degradation of the monitored web services.

6. R.BEN HALIMA , K.DRIRA , M.JMAIEL

A QoS-driven reconfiguration management system extending Web services with self-healing properties

Rapport LAAS No07076

Workshop on Information Systems & Web Services (ISWS 2007 - WETICE 2007), Paris (France), 18-20 Juin 2007, pp.339-344

This paper addresses QoS management for self-healing Web services. The objective is to provide a healing framework based on service monitoring and architectural-level repair actions. We address these topics in the context of the European project WS-DIAMOND. We implemented and assessed a connector-based healing layer capable of intercepting, analyzing and enhancing SOAP traffic and message contents with QoS data. Our framework supports Service Monitoring and dynamic run-time reconfiguration based on reflective programming.

7. R.BEN HALIMA , M.JMAIEL , K.DRIRA

Une approche orientée règle pour la spécification formelle des architectures dynamiquement configurables

Rapport LAAS No07075

Conférence Internationale sur les NOvelles TEchnologies de la REpartition (NOTERE 2007), Marrakech (Maroc), 4-8 Juin 2007, pp.405-412

Dans ce papier, nous traitons le problème de la conception formelle des systèmes logiciels distribués dynamiquement reconfigurables. Pour compléter les approches de reconfiguration comportementale souvent adoptées, nous introduisons la reconfiguration architecturale. Cette technique permet de construire dynamiquement l’architecture d’un système logiciel et de l’adapter à l’évolution de l’activité qu’il soutient. Pour formaliser les différentes instances d’architectures et styles, nous spécifions en Z les entités logicielles et leurs liens d’interaction par des schémas. Nous spécifions par des opérations Z, les règles qui régissent l’évolution dynamique des architectures de façon conforme à un style architectural spécifié aussi selon la même technique. Nous illustrons notre approche à travers les propriétés de dynamicité des logiciels de support pour les activités coopératives distribuées. Pour modéliser l’architecture, nous adoptons une approche orientée composant et nous distinguons différents modes d’interaction (pull/push) entre les différents composants. Notre approche est soutenue par un environnement logiciel de simulation visuelle qui interprète les spécifications Z. Nous dispensons ainsi les concepteurs de la maîtrise de ce formalisme et nous leur offrons une interface "boite et traits" qui fait référence dans la conception informelle des architectures. Notre environnement de simulation est couplé avec l’outil Z/EVES. Il gère les spécifications Z au format de Z/EVES tout en vérifiant leur complétude et leur exactitude. Il interprète aussi visuellement les spécifications architecturales codées au format Z/EVES.

8. R.BEN HALIMA , M.JMAIEL , K.DRIRA

Graphical simulation of the dynamic evolution of the software architectures specified in Z

Rapport LAAS No05470

International Workshop on Principles of Software Evolution (IWPSE'2005), Lisbonne (Portugal), 5-6 Septembre 2005, pp.45-48

This paper provides a graphical simulator that enables to apprehend the dynamic of components-based software architectures based on their formal specification. The simulator initially accepts (as an input) an already validated Z specification using the Z/EVES tool. Then, it generates graphical entities, according to the UML notation, representing software’s components and their connectors. Thereafter, the user may generate architecture instances by adding components and connections between them. Architecture instances can be updated by destroying components/ connections or by modifying their interconnections. The user actions are checked through the formal specification of the architectural style.