Developing software reliability growth model for multi up gradations with faults of different severity and related release time problem

In order to deal with the stiff competition and survive in the market, software companies need to keep upgrading their software by bringing new changes and improvising it. By adding new functionalities company aims to improve the software performance and functionality. But software up gradation does not always lead to quality enhancement, there is a possibility of adding new faults while up gradation, which causes rise in total amount of faults. In this work a software reliability growth model (SRGM) has been proposed for multi up gradations with faults of different severity and related release time problem. An optimization equation for cost model is described to determine the optimum time of release in multi up-gradation of software. Here we classify the faults into three different types depending upon the effort and time consumed for their removal; simple, hard and complex faults. We validated this model on a data set for software with four releases.