To implement abstract business processes, elementary#R##N#services are selected for each abstract task. Because of#R##N#uncertainties of Quality of Service (QoS) values during execution,#R##N#services may become faulty and cause the violation of endto-#R##N#end awaited constraints. Additionally, due to the dynamic#R##N#nature of service systems, several environment changes may#R##N#occur at run-time. In fact, services can join or leave the system#R##N#or change their offerings. To deal with possible changes and#R##N#maintain the feasibility of the selected solution, enabling dynamic#R##N#service selection during execution is essential. This is not a#R##N#trivial task especially in the presence of several constraints#R##N#and dependencies between services namely QoS and temporal#R##N#constraints. Existing approaches do not consider the specificities#R##N#of temporal properties and usually handle violations after they#R##N#have occurred. In this paper, a novel proactive dynamic service#R##N#selection approach is proposed to deal with changes during#R##N#execution while considering both QoS and temporal constraints.#R##N#Experiments show that, by using our approach, faults can be#R##N#successfully handled in a reasonable time while guaranteeing#R##N#overall constraints.
['Ikbel Guidara', 'Imane Al Jaouhari', 'Nawal Guermouche']
Dynamic Selection for Service Composition Based on Temporal and QoS Constraints