The Research On QoS-Based Semantic Web Services Monitoring

With the sharp increasing of the number of web services, QoS (Quality of Service) attributes of a web service become very important in the distinction of same or similar semantic web services. The values of QoS attribute which provided by service providers or users maybe have low credibility due to the lack of verification by a third party organization. In order to ensure the impartiality and objectivity of QoS attribute values, a semantic web services monitoring system which is independent of service providers or users need to be developed.Traditional web services monitoring system only focuses on the generic QoS attributes, which can not support the monitoring of new QoS or domain-specific QoS attributes. Domain-specific QoS attributes are of great use in the evaluation and selection of web services.This paper describes mechanism for execution monitoring of semantic web services, based on OWL-S. We develop an ontology of monitoring events based on OWL, which defines various events for QoS monitoring. The monitoring system can support generic and domain-specific QoS attributes monitoring based on event ontology.Based on the modification of semantic web services execution engine, the execution engine can emit QoS monitoring events during the period of execution. The monitoring system can calculate QoS attribute values by the detection and analysis of the events. Finally the monitoring system uses these monitoring values to update the web services information which store in the service registration center. The service selection can select more suitable web service for user based on the new QoS attribute values. In this paper, we design and implement a QoS-based semantic web services monitoring system, which support generic and domain-specific QoS attributes monitoring and calculation.