Software Release and Patching Time with Warranty Using Change Point

Abstract

Software reliability growth models (SRGMs) are supportive for software developers and well acknowledged by industry experts. Researchers have examined the reliability growth of software during testing and operational phases and projected many mathematical models for forming reliability measures of software. SRGMs have been proposed in literature to measure the quality of software and used to find optimal release time of software at minimum cost. It is a common observation that as the testing progresses, the fault detection and/or removal rate changes based on many factors. The point at which change in the fault detection rate takes place is known as change point. Changes in testing environment and testing strategy are some of the major reasons behind this change. Early software release increases the chance of a software product with significant number of defects due to which the manufacturer has to bear post-release cost of fixing the faults. On the other hand, late release may result in loss of market opportunity and dissatisfied customers. Nowadays, releasing early and updating by providing patches in the operational phase are in trend in software industry. Also to provide assurance for software reliability, organizations provide warranty on their product. During the warranty phase, organizations promise their customers for either repairing or replacing in case of defect encounter. Keeping all the above issues in mind, in this paper we have formulated the generalized cost model to determine the optimal software release and patch time to minimize overall cost based on change point under warranty. Numerical illustration is provided to authenticate the anticipated cost model.