Distribution of Control Via Automation Networks Using the Producer/Consumer Model, 1998 Process Control, Electrical & Info. Conference Proceedings

Today users are demanding more from their control systems, and consequently, from the networks that connect the system together. They want more or better diagnostics, less downtime, and reduced installation and maintenance costs. At the same time, they are demanding improved throughput. With increased functionality comes increased traffic (data) on the control system network. Today’s automation networks, most of which are source/destination based, cannot offer the required functionality and accommodate the increased traffic flow, thus restricting system capabilities and productivity improvements. Increased demands on automation networks have forced the adoption of a newer network model – one that provides greater functionality, makes more efficient use of network bandwidth, and increases information flow, all while reducing traffic on the wire. Unfortunately, much of the discussion to date about networks has focused on baud rates, protocol efficiency, and physical characteristics (i.e. type of wire used, distance capabilities, etc.). In reality, it’s more complex than that. Available diagnostics, messaging types and throughput must all be considered when evaluating a control system network. The most important factor affecting these capabilities in the control environment is the network model. The source/destination model used for the past two decades can no longer meet today’s network needs. The only model available today that can meet these demanding requirements and allows for future migration is the producer/consumer network model.