Considering alternative strategies for value sustainment in systems-of-systems

Systems of Systems (SoSs) operating in an uncertain world must overcome a variety of challenges in order to sustain value delivery over time. This paper describes strategies for value sustainment, using an application of the “wave model” to represent time-varying SoS Engineering (SoSE) activities and opportunities for SoS-change. A Maritime Security (MarSec) SoS case study is described, and simulation-based Era Analysis is used to evaluate SoS alternatives through different operational environments for an assumed 8-year time frame. Eight SoS designs are evaluated and compared across four strategies in terms of accumulated utility, discounted cost, and total down time. The four value sustainment strategies are: (1) self-recovery, the SoS is not changed (i.e., relating to survivability/robustness); (2) changes in the design of the SoS are allowed (i.e., relating to changeability); (3) changes in the architecture of the SoS are allowed (i.e., relating to evolvability) once, or (4) three times in the eight years. The results provide an example of how quantitative approaches can be used to gain insights into tradeoffs in how SoS architects can create value-sustainable SoSs for the long run.