Software reliability assessment is important to evaluate and predict the reliability and performance of software system. This book introduces the control mechanism based on the cumulative quantity observations of interval domain data using mean value function of Burr type XII model, which is based on Non-Homogenous Poisson Process (NHPP). Sequential Analysis of Statistical science could be adopted in order to decide upon the reliability or unreliability of the developed software very quickly. The procedure adopted for this is, Sequential Probability Ratio Test (SPRT). And also discussed the performances of real time software failure datasets based on time domain using Burr type III & Burr type XII SRGMs.