| A framework for systems integration complexity measurement is developed that includes not only the measures of systems complexity but also a systems architecting process model. An appropriate combination of the rational systems engineering process and the experience-based heuristics approach is suggested as a systems architecting process model. Two uncertainty-based systems complexity measures, Structural Complexity and Interface Complexity, were developed based on Shannon's Information Theory, and these are derived from the systems architectural attributes such as the number of functions/sub-functions, the number of interfaces and their interface distances. The framework is demonstrated with a real world example, a global telecommunications system, to show the feasibility and applicability of the proposed approach.; This framework can be used as a design tool for selection of systems architectural attributes and design trade off and sensitivity analysis and as a communications tool with customers and between project members. Once the 'threshold complexity values' are empirically validated against the variables such as resource requirements, cost, schedule, and risk, the proposed complexity measures could also be used as a prediction and estimation tool.; A survey experiment was conducted with systems engineers and program managers, showing that the proposed complexity measures are objective, straightforward to calculate, and easily automatible. A majority of respondents believed that the proposed framework can help them, to name a few, to (1) Identify and control system interfaces; (2) Reduce development risk for the system; (3) Allow a comparison of alternative designs; (4) Improve the state-of-the-art in the building of systems; (5) Do better in systems integration; and (6) Understand how to reduce complexity. |
