Real-Time I/O Performance Metrics and Tests for Industrial Ethernet
James D. Gilsinn
Real-time input/output (I/O) communication over Ethernet is still fairly new in the industrial environment. There are many questions about the reliability and performance that have to be answered before industrial Ethernet can be utilized in most manufacturing plants. Similar questions are being asked in the information technology (IT) environment now that real-time communications are being used more heavily in such applications as real-time broadcasts and voice over the Internet Protocol (VoIP). Performance metrics and tests for IT infrastructure equipment have been used for many years, but now with real-time communications being used more, users are asking whether their desktop, laptop, or palm computer can handle the performance requirements of these network intensive applications. These same questions can be asked of industrial equipment as well. Can a Programmable Logic Controller (PLC), Distributed Control System (DCS), or Supervisory Control and Data Acquisition (SCADA) system handle the performance requirements for real-time I/O communications over industrial Ethernet? The National Institute of Standards & Technology (NIST) and the Open DeviceNet Vendor Association (ODVA) are developing a set of metrics and tests for real-time I/O performance of industrial devices. These will allow the user to have a common language and method to test different devices. Since performance metrics and tests have been used in the IT environment for many years, many of the same tools and experience can be utilized when developing metrics and tests for industrial Ethernet equipment. Last March, at the ODVA EtherNet/IP Interoperability Demonstration, a basic set of performance tests was conducted and data was collected about the performance of the devices that participated. A second interoperability demonstration was conducted in January of 2004 where a more substantial set of performance tests were conducted and data was collected. The performance metrics and tests used at these two demonstrations, as well as some of the data collected, will be discussed in this paper.
Real-Time I/O Performance Metrics and Tests for Industrial Ethernet, Proceedings of ISA Automation West 2004, Long Beach, CA, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=822490
(Accessed June 6, 2023)