An EDF-based Swapping Approach to enhance support for asynchronous real-time traffic over EtherCAT networks

EtherCAT is a real-time Ethernet protocol for factory automation applications that enables periodic data exchange with cycle times of a few microseconds thanks to the capability to process frames “on-the-fly”. EtherCAT does not provide efficient mechanisms for enabling the transmission of asynchronous real-time data from slave nodes. This paper proposes an EDF-based Swapping Approach that allows slaves to send real-time asynchronous traffic over EtherCAT networks in an efficient way, while maintaining the interoperability with standard devices. The paper describes the EDF-based Swapping Approach and presents a comparative performance evaluation with both the EtherCAT standard and an approach in the literature that exploits CAN-Like arbitration.

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