Workflow systems orchestrate various business tasks to attain an objective. Web services can be leveraged to handle individual tasks. Before anyone intends to leverage service components, it is imperative and essential to evaluate the trustworthiness of these services. Therefore, choosing a trustworthy service has become an important decision while designing a workflow system. Trustworthiness can be defined as the likelihood of a service functioning as it is intended.
Selection of a service that satisfies business goals involves collecting relevant information such as security mechanisms, reliability, performance and availability. It is important to arrive at total trustworthiness, which incorporates all of the above mentioned multi-facet values relevant to a service. These values can be gathered and analyzed to derive the total trustworthiness of a service. Measuring trustworthiness of a service involves arriving at a suitable value that would help an end-user make a decision for the given business settings.
The primary focus of this thesis is to gather relevant details and measure trustworthiness based on inputs provided by the user. A conceptual model was developed after extensive literature review to identify factors that influence trustworthiness of a service. A mechanism was created to gather concept values for a given service and utilize those values to calculate trustworthiness index value. A proof-of-concept prototype was also developed. The prototype is a web-based application that implements the mechanism to measure the trustworthiness of the service. The prototype was evaluated using a scenario-based analysis method to demonstrate the utility of the trustworthiness mechanism using three different scenarios. Results of the evaluation shows that trustworthiness is a multidimensional concept, the relevant conceptual values can be collected, a trustworthiness index value can be calculated based on the gathered concepts, and a trustworthiness index can be interpreted to select the most relevant service for a given requirement
