Evaluating COTS Components Using Gap Analysis

In current COTS software components evaluation methods, the resulting scores only represent relative ranking of the alternatives and the differences in their value does not give any indication of their relative superiority. Based on gap analysis theory, a new evaluation approach is proposed in this paper. The functional and non-functional gap between COTS components and system requirements are identified through function point analysis and corresponding adjustment cost is measured by count of function points. Besides adjustment cost, purchase cost is also a part of the total cost for adopting a COTS product. The fitness of a COTS product to requirements is defined as the ratio of the functional size of target system to the total cost of COTS that is also measured in functional size.