For large software systems, the maintenance phase tends to have comparatively much longer duration than all the previous life-cycle phases taken together, obviously resulting in much more efforts. A good measure of software maintainability can help better manage the maintenance phase effort. Software maintainability cannot be adequately measured by only source code or by documents. The readability and understandability of both, source code and documentation should be considered to measure the maintainability. This paper proposes an integrated measure of software maintainability. The paper also proposes a new representation for rule base of fuzzy models, which will require less space for storage and will be efficient in finding the results in the simulation. The proposed model measures the software maintainability based on three important aspects of software- Readability of Source Code (RSC), Documentation Quality (DOQ), and Understandability of Software (UOS). Keeping in view the nature of these parameters, a fuzzy approach has been used to integrate these three aspects. A new efficient representation of rule base has been proposed for fuzzy models. This integrated measurement of software maintainability, which to our knowledge is first attempt to quantify integrated maintainability, is bound to be better than any other single parameter maintainability measurement approach. Thus the output of this model can advise the software project managers in judging the maintenance efforts of the software.
