AN INTRODUCTION TO POPULATION PROTOCOLS

The population protocol model describes a collection of tiny mobile agents that interact with one another to carry out a computation. The agents are identically programmed finite state machines. Interactions between pairs of agents cause the two agents to update their states. These interactions are scheduled by an adversary, subject to a fairness constraint. Input values are initially distributed to the agents, and the agents must eventually converge to the correct output value. This framework can be used to model mobile ad hoc networks of tiny devices or collections of molecules undergoing chemical reactions. We survey results that describe what can be computed in various versions of the population protocol model.