Responsibility modeling for identifying sociotechnical threats to the dependability of coalitions of systems

With the rise of cloud computing and system-of-systems we are entering an era where mission critical services and applications will be dependent upon `coalitions-of-systems'. Coalitions-of-systems (CoS) are a class of system similar to systems-of-systems but they differ in that they interact to further overlapping self-interests rather than an overarching mission. Assessing the sociotechnical dependability of CoS is an open research question of societal importance as existing sociotechnical dependability analysis techniques typically do not assess threats associated with coalition partners reneging on responsibilities or leaving a coalition. We use a cloud computing based case study to demonstrate that a responsibility modeling based risk analysis approach enables the identification of these threats. We provide first evidence that inspecting the distribution of liabilities among coalition partners may indicate the fragility of overlapping self-interests.