eprintid: 2586 rev_number: 7 eprint_status: archive userid: 6 dir: disk0/00/00/25/86 datestamp: 2015-02-10 14:02:29 lastmod: 2015-07-24 12:28:15 status_changed: 2015-02-10 14:02:29 type: book_section metadata_visibility: show creators_name: Tschaikowski, Max creators_name: Tribastone, Mirco creators_id: max.tschaikowski@imtlucca.it creators_id: mirco.tribastone@imtlucca.it title: Generalised communication for interacting agents ispublished: pub subjects: QA75 divisions: CSA full_text_status: none keywords: bandwidth sharing; process algebra; semantics of communication abstract: Process algebra for quantitative evaluation are based on either of the two following mechanisms for communication: binary, where a channel is shared by exactly two agents, or multiway, where all agents sharing a channel must synchronise. In this paper we consider an intermediate form which we call generalised communication, where only m agents out of n potentially available are involved in the communication. We study this in the context of the stochastic process algebra PEPA, of which we conservatively extend the syntax and semantics. We give an intuitive interpretation in terms of bandwidth assignments to agents communicating over a shared medium. We validate this semantics using a real implementation of a simple peer-to-peer protocol, for which our performance model yields predictions with high accuracy. We prove a result of lumpability that exploits symmetries between identical communicating agents, yielding good scalability of the underlying continuous-time Markov chain (CTMC) with respect to increasing population levels. Furthermore, we present an algorithm that derives the lumped chain directly, without having to generate the full CTMC first. date: 2012-09 date_type: published publisher: IEEE pagerange: 178-188 event_title: Quantitative Evaluation of Systems (QEST), 2012 Ninth International Conference on id_number: 10.1109/QEST.2012.16 refereed: TRUE isbn: 978-0-7695-4781-7 book_title: Proceedings of the 9th International Conference on Quantitative Evaluation of Systems (QEST) official_url: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6354646&isnumber=6354626 citation: Tschaikowski, Max and Tribastone, Mirco Generalised communication for interacting agents. In: Proceedings of the 9th International Conference on Quantitative Evaluation of Systems (QEST). IEEE, pp. 178-188. ISBN 978-0-7695-4781-7 (2012)