Life time warranty cost model for software with imperfect error rectification

The optimum release time or total testing time of a software product subject to the desired quality and total testing cost is an important issue. In this paper an attempt is made to extend the software cost model proposed by William et al. by considering the cost factors such as test effort, cost of imperfect rectification of errors and life time warranty cost. The cost of software testing is the sum of the cost incurred due to initial testing cost, cost of testing the software per unit time and warranty cost. For this model the optimum release time and optimum release policy are proposed by minimizing the cost function subject to the desired reliability levels under the situation: (i) when warranty is provided to retain the reliability level promised at the time of software release (ii) when warranty is provided to increase the reliability level from the time of software release.