Collective Adaptation in Process-based Systems

A collective adaptive system is composed of a set of heterogeneous, autonomous and self-adaptive entities that come into a collaboration with one another in order to improve the effectiveness with which they can accomplish their individual goals. Self-adaptation of individual elements in the context of a collective adaptive system – for instance, to respond to some critical or emergent situation – may break the ongoing collaboration or otherwise negatively affect the other participants. That is one reason why adaptation in such systems must be itself collective. In this paper, we offer a characterization of ensembles, as the main concept around which systems that exhibit collective adaptability can be built. Our conceptualization of ensembles enables to define a collective adaptive system as an emergent aggregation of autonomous and self-adaptive processbased elements. To elucidate our approach to ensembles and collective adaptation, we draw an example from a scenario in the urban mobility domain, we describe an architecture that enables that approach, and we show how our approach can address the problems posed by the motivating scenario.