|Service-Oriented Computing is undoubtedly discerned as a latest emerging paradigm for distributed computing in order to change the way of design, delivery and consumption of software applications. A great transition happened to present a new paradigm namely Service due to adding action to knowledge. There is a necessity to build a foundation with intention to next generation of service management systems employing Web Services as dominant technology in SOC. Accordingly there will be Web Service Management System in which four core components are identified: service optimization, service composition, service change and service trust. Since trust has been a key factor holding industry and business back from adopting services, this study tries to concentrate on latter case i.e. service trust and its impact in the service computing.
Moreover, the number of available services to fulfill users’ requirements is increasing on the fly. Considering this fact, service users face two challenges: First, selecting the most desired service candidates among the discovered services and second, deciding on the extent to which they can trust selected service candidates with respect to the claimed Quality of Service (QoS) criteria. There is still an inevitable need to investigate services behavior considering the fact that services are inherently priori information in their collaborations. Service users should be enabled to make sure about accuracy of perceived service behavior against the claimed one by service provider. The aim of this research is to evaluate service trustworthiness with respect to consensus protocol. Since trust is a multi-facet approach, its evaluation should be multi-criteria based and fuzzy logic concepts are utilized to achieve it. This research intends to: present comparative evaluation of state-of-the-art approaches in trustworthy service computing; investigate and develop new approach to evaluate service trust; and prove the efficiency of the proposed approach based on experimental results.