A communication protocol for hard and soft real-time systems

The distributed real-time community is mainly divided into two camps: hard real-time and soft real-time; hybrid systems have been considered but not to any great extent. In this paper we propose a hybrid communication protocol, which forms a foundation for interconnection of nodes in a distributed hybrid real-time system. The protocol will enable both hard and soft real-time frames on a broadcast communication bus, yet still guarantees the hard real-time behaviour. The protocol will utilise the communication bandwidth more efficiently, which is relevant to cost-sensitive embedded applications.