Design principles and measurable service oriented usability

In this paper, the service oriented software usability, which is defined in the ISO/IEC 9126 standards as a number of nonfunctional software quality characteristics, is shown to be measurable by given design principles. The purpose of the study is to develop an approach to (1) provide measurable indexes for usability characteristics and (2) obtain the measurable indexes from previously experienced design principles. The practical works are related to a mapping table, a weighting policy, and a normalization process. We assumed five design principles for service oriented applications and then mapped them to the characteristics as an example, and at last we formally proved the soundness of the approach.