Abstract
Web services are software modules that provide interoperability over a network. Web services provide Web service users platform independence while using software. It enables businesses to collaborate by using Web services from Web service providers. Estimating a Cost of Service (CoS) is essential when pricing, selecting, and monitoring a Web service. The concept of cost is not restricted to financial value of technology hardware and software. The cost concept can also include time, usability, and maintenance. Cost of a Web service can be estimated by identifying the attributes of cost from the perspective of different stakeholders such as Web service provider, Web service consumer, Web service repository moderator, and Web service policy maker. In addition, analyzing different roles in Service Oriented Architecture (SOA) will further provide more knowledge about different perspectives of cost concepts in SOA. This paper addresses the essential attributes of estimating cost of a Web service. Moreover, this paper specifies attributes of measuring CoS, defines these attributes, and defines metrics and units of these attributes. Additionally, it provides further hierarchy classification of Web service cost concepts. It also provides a model for evaluating Web service cost based on different cost criteria. By measuring CoS, Web service stakeholders will be able to estimate an accurate value to the CoS.