Abstract
Software complexity estimation is an important activity to software development life-cycle such as in terms of effort, cost and size. A lot of estimation models were proposed in the literature but they do not consider the new paradigm shift in software development service-oriented architecture (SOA). SOA is a new style of software architecture that has six principles like standard interface (contract) which allows building technology-independent applications that can interoperate. Function Point (FP) metrics were designed to consider functional requirements (complexity) instead of lines of code, which is enriched by Use Case Point (UCP), a software estimation technique proposed to estimate the software size and effort for software development projects of object-oriented systems. However, estimation techniques for Service-Oriented Architecture (SOA) are still not investigated well. Generally the demanded is having global view by relating function point methods with SOA design principles so this is an attempt to provide this view. As UML use case and activity models are widely recognized for its easy of communication, this paper has adopted them for estimating service-based systems complexity as a source of information for system under estimation in high level models. The proposed technique is compatible to the design principles of SOA and provides a systematic and formal way for complexity estimation. Courseware management service-based system is used as case study to evaluate the proposed technique.