Factors Influencing System-of-Systems Architecting and Integration Costs

Today’s need for more complex, more capable systems in a short timeframe is leading more organizations towards the integration of existing systems into networkcentric, knowledge-based system-of-systems (SoS). Software and system cost model tools to-date have focused on the software and system development activities of a single software system. As we view the new SoS architectures, we find that the effort associated with the integration of these SoSs is not handled well, if at all, in current cost models. USC’s Center for Software Engineering (CSE) began work on a SoS cost model, the Constructive SoS Integration Model (COSOSIMO), in late 2003. This model has evolved using feedback obtained from USC CSE affiliates and other experts in industry and academia. This paper presents an overview of the COSOSIMO cost model, descriptions of the size drivers and cost factors currently in the model, a summary of survey feedback received from USC CSE affiliates and other interested experts from industry, and the impact of survey findings on the current COSOSIMO cost model. It concludes with future plans for the COSOSIMO model. History of COSOSIMO Why a COSOSIMO? We are seeing a growing trend in industry and DoD to “quickly” incorporate new technologies and expand the capabilities of legacy systems by integrating them with other legacy systems, Commercial-Off-the-Shelf (COTS) products, and new systems. With this development approach, we see new activities being performed to define the new architecture, identify sources to either supply or develop the required components, and then to integrate and test these high level components. Along with this “system-of-systems” (SoS) development approach, we have seen a new role in the development process evolve to perform these activities: that of the Lead System Integrator (LSI). Today, there are fairly mature tools to support the estimation of the effort and schedule associated with the lower-level SoS component systems. For software development activities, there are the COCOMO II, Cost Xpert, Costar, PRICE S, and SEER-SEM cost models. At the single system level, there is COSYSMO to estimate the system engineering effort and PRICE H and SEER-H to estimate hardware development costs. For COTS implementation and integration, there is COCOTS to estimate the effort associated with the assessment,