A Production Cell Controlled by Dependable Multiparty Interactions

The goal of this paper is twofold. Firstly, we present a way of extracting interactions between objects and enclosing them by using multiparty interactions. In a multiparty interaction, several executing threads somehow \come together" to produce an intermediate and temporary combined state, use this state to execute some activity, and then leave this interaction and continue their normal execution. This kind of approach has been considered in several papers but all of them have failed to describe how failures in one or more participants of the multiparty interaction can be dealt with. In this paper, general object-oriented schemes for constructing dependable multiparty interactions (DMIs) in a distributed environment are presented. Secondly, we show how one of these schemes can be used to program a system in which multiparty interactions are more than simple synchronisations or communications. We have designed and implemented a controlling software for a fault-tolerant production cell model developed by Forschungszentrum Informatik, Karlsruhe, Germany.