Abstract: Maintainability has always been an elusive concept. Its correct measurement or evaluation is a difficult exercise because of the various potential factors affecting software maintainability. Software maintainability involves external software quality attributes that evaluate the design complexity and effort required for maintaining software. The support provided by software maintainability is significant during development life cycle and quality assurance. The key focus of this review paper is an organized study of maintainability taking into consideration the view provided by its sub factors along with metrics implementation of software maintainability. The aim is to support the maintenance process and facilitate the formation of improved quality software. This paper accomplishes a systematic literature review to study widespread facts of maintainability research, its feature factors and related measurements. A comparative analysis on software maintainability models developed by various researchers/area experts including their contribution and limitation is also presented. In the end our effort is to find the known wide ranging and complete model or framework for quantifying the maintainability of software at an early stage of software development life cycle.
Keywords: Software Maintainability, Maintainability Evaluation, Object Oriented Design, Software Quality, Software testing.