(A) feature based software modelling by dependency alignment for levelled maintenance

Abstract

While the way we build software affects significantly its maintenance in terms of the effort and cost, the experience level of the maintainer in software acquirers`` organization is also one of concerns. In this context, often the maintainer is the user of the system. Unfortunately, it is quite possible to lose the trustworthiness of the software due to the inexperience of the maintainer, especially when the maintainer is without the help of original developers. For example, many organizations including bank, government, and military have their own task force team to maintain their delivered software. Preserving the trustworthiness of such software is as important as developing the software. While the way we build software affects significantly its maintenance in terms of the effort and cost, the experience level of the users who are maintaining it is also one of concerns. Unfortunately, it is quite possible to lose the trustworthiness of the software due to the inexperience of the maintaining users, especially when those users are without the help of original developers. One remedy for controlling the effect of the maintainer``s modifications to the trustworthy software is to restrict the access to software parts (modules) according to the experience level of users. For such remedy to be successful, the software should be constructed in such a way that its parts under maintenance affect others as less as possible, in principle. We propose Feature Based Modelling (FBM): an approach to software construction aligning the dependencies in one direction among software parts restrictively so that they are allocated to maintaining users depending on their experience level. FBM decompose the software into features based on functionalities and order them by essentiality that indicates the degree of the criticality of each feature. The dependencies of the design units and code modules are ordered in such a way that the less essential one is dependent on more essential on...