Optimal resource allocation for cost and reliability of modular software systems in the testing phase

Reliability is one of the most important quality attributes of commercial software since it quantifies software failures during the development process. In order to increase the reliability, we should have a comprehensive test plan that ensures all requirements are included and tested. In practice, software testing must be completed within a limited time and project managers should know how to allocate the specified testing-resources among all the modules. In this paper, we present an optimal resource allocation problem in modular software systems during testing phase. The main purpose is to minimize the cost of software development when the fixed amount of testing-effort and a desired reliability objective are given. An elaborated optimization algorithm based on the Lagrange multiplier method is proposed and numerical examples are illustrated. Moreover, sensitivity analysis is also conducted. We analyze the sensitivity of parameters of proposed software reliability growth models and show the results in detail. The experimental results greatly help its to identify the contributions of each selected parameter and its weight. The proposed algorithm and method can facilitate the allocation of limited testing-resource efficiently and thus the desired reliability objective during software module testing can be better achieved. (c) 2005 Elsevier Inc. All rights reserved.