The computational power of population protocols

We consider the model of population protocols introduced by Angluin et al. [AAD+ 04], in which anonymous finite-state agents stably compute a predicate of the multiset of their inputs via two-way interactions in the family of all-pairs communication networks. We prove that all predicates stably computable in this model (and certain generalizations of it) are semilinear, answering a central open question about the power of the model. Removing the assumption of two-way interaction, we also consider several variants of the model in which agents communicate by anonymous message-passing where the recipient of each message is chosen by an adversary and the sender is not identified to the recipient. These one-way models are distinguished by whether messages are delivered immediately or after a delay, whether a sender can record that it has sent a message, and whether a recipient can queue incoming messages, refusing to accept new messages until it has had a chance to send out messages of its...

• Type: Journal
• Year: 2006
• Where: CORR
• Authors: Dana Angluin, James Aspnes, David Eisenstat, Eric Ruppert
• Keywords: CORR 2006, Education, Model, Population Protocols, Two-way Interaction