A Catalogue of Decentralised Coordination Mechanisms for Designing Self-Organising Emergent Applications

There is little or no guidance to systematically design a selforganising emergent solution that achieves the desired macroscopic behaviour. This paper describes decentralised coordination mechanisms such as digital pheromones as design patterns, similar to patterns used in mainstream software engineering. As a consequence, a structured consolidation of best practice in using each coordination mechanism becomes available to guide engineers in applying them, and to directly decide which mechanisms are promising to solve a certain problem. As such, self-organising emergent solutions can be engineered more systematically, which is illustrated in a packet delivery service application. This document includes extensive pattern descriptions for digital pheromones, gradient fields, market-based coordination, tag-based coordination, and token-based coordination.