A trade-off method between cost and reliability

Proposes a method for estimating the development cost of a software module, taking into account the target level of reliability for that module. Our objective is to establish a basis for a model to guide a primary trade-off between cost and reliability during the design phase of the development of a modular software system. The line of argument developed is that the operational reliability of a software module can be linked to the effort spent during the testing phase; a higher level of desired reliability requires more testing effort and, consequently, costs more. A decomposition technique is used to estimate the cost of development, based on an estimate of the number of faults to be found and fixed in the required reliability, using data obtained from the requirement specification and historical data. The proposed model is easy to understand and suitable for use by project managers