[ecoop-info] Open PhD thesis funded in the framework of the Marie-Curie European ITN Relate: "Verifying Web Services Composition"

[Benoit Combemale]

A PhD thesis is available at the INRIA Rennes Bretagne Atlantique Research Center in the team-project Triskell (http://www.irisa.fr/triskell/), Rennes, France.
This PhD thesis should be funded in the framework of the Marie-Curie European ITN Relate.

* Title: Verifying Web Services Composition *
Scientific advisor: Benoit Baudry (benoit.baudry at inria.fr), and supervisor: Benoît Combemale (benoit.combemale at irisa.fr)

Description:
New software intensive systems will be more and more realized as an interconnection of services distributed on the internet or on remote clouds. Web applications that are build as a composition of individual services represent one incarnation of this future trend. From a software development perspective, it is possible to imagine that these applications will be modeled as (i) QoS contracts expressing expected quality properties on individual services and (ii) a workflow specifying temporal dependencies between services. To deploy these applications, either some services will exist that will conform to the required properties, or new services will be developed.

In this context we are interested in design time and runtime validation of service composition. At design time we assume an abstract model of the composite web application ans we want to use it for simulation and model checking as well as test generation. Exhaustive verification on the model can be used to verify properties such as causality and temporality. This requires the construction of a generic bridge between the model and several verification tools. For all aspects of the web application that cannot be captured in the abstract model, e.g. QoS, we will test. Unit testing consists in investigating test generation techniques to verify individual services w.r.t expected functionality and expected quality of service. Integration testing consists in testing that the workflow can be correctly deployed w.r.t individual QoS contracts.

The major issue for the verification of composite web services is the volatility of services. New services that satisfy expected QoS can emerge on the web, existing services can disappear. Consequently, composite web services have to constantly monitor available services, test them online and sometimes reconfigure themselves accordingly. Because of these runtime reconfigurations, it is necessary to maintain a verification activity at runtime. At this stage we cannot assume the existence of a model, thus it is first necessary to infer a corresponding model. This model can in turn be used for the same type of verification that were performed at design time.

Contacts: Benoit Baudry (benoit.baudry at inria.fr) and Benoit Combemale (benoit.combemale at irisa.fr)

** All jobs and internships available in the team-project Triskell at http://www.irisa.fr/triskell/jobs