Motivated by distributed implementations of game-theoretical algorithms, we study symmetric process systems and the problem of attaining common knowledge between processes. We formalize our setting by defining a notion of peer-to-peer networks and appropriate symmetry concepts in the context of Communicating Sequential Processes (CSP) [1]. We then prove that CSP with input and output guards makes common knowledge in symmetric peer-to-peer networks possible, but not the restricted version which disallows output statements in guards and is commonly implemented. Our results extend [2].
Springer
Lecture Notes in Computer Science
International Conference on Mathematics of Program Construction
Networks and Optimization

Witzel, S. A. (2008). Symmetric and Synchronous Communication in Peer-to-Peer Networks. In Proceedings of the 9th International Conference on Mathematics of Program Construction (MPC08) (pp. 404–421). Springer.