COCOTS: a COTS software integration cost model - model overview and preliminary data findings

As the use of commercial-of-the-shelf (COTS) components becomes ever more prevalent in the creation of large software systems, the need for the ability to reasonably predict the true lifetime cost of using such software components grows accordingly. In using COTS components, immediate short-term gains in direct development effort & schedule are possible, but usually as a trade-off for a more complicated long-term post-deployment maintenance environment. This paper discusses a COTS cost model being developed as an extension of the COCOMO II [1] cost model. COCOTS attempts to predict the lifecycle costs of using COTS components by capturing the more significant COTS risks in its modeling parameters. The current state of the model is presented, along with some preliminary findings suggested by an analysis of calibration data collected to date. The paper concludes with a discussion of the on-going effort to further refine the accuracy and scope of COCOTS.