Fatemeh Fouladfar - Department of Information Technology, Faculty of Engineering University of Isfahan, Iran
Ahmad Baraani - Department of Computer, Faculty of Engineering University of Isfahan, Iran

Service Oriented Architecture is a new and evolving approach that makes building distributed applications and presenting software performance in form of componentsthat can be discovered in network using loose connection and high independence. The technology that enables the creation and sharing of these autonomous pieces of software are web services. The application of web services technology in areas such as e-commerce and e-learning is on the rise. The problem of selecting the best web service among the candidate web services is one of the major challenges in open and dynamic environments in which new consumers, providers and servicesmay continuously be added to the system or leave the system. The criterion that is mostly used for selecting web services in other studies is the quality of service. However, it is possible that a provider exaggerates the characteristics of its service quality in order to obtain more consumers and thus make more profit. Therefore, in case of exaggerated descriptions by dishonest providers, web service selection algorithm will fail. Hence, if the service quality criterion is to be used in theselection of web services, a solution must be provided to address the exaggerated descriptions challenge. To this end, in this study, a new trust model has been developed for the selection phase that considers trust and reputation along with the quality of service as selection criteria. In this model various aspects of trust will be examined in order to cope with the impact of misleading feedback. Furthermore, personalized reputation is used as well as general reputation. This model uses social network analysis in order to provide a personalized offer. Finally, a selection procedure based on web services trust is presented in which the proposed model is used. By taking intoaccount the relationship of trust between all the components involved in the composition (services, providers, and consumers), a web service will be offered to the user which is the most reliable one. Assessments made indicate the high tolerability of this model against fake descriptions compared to other models

Trust, Reputation, Quality of Service, Service-Oriented Architecture, Web Service