Design and Benchmarking of the Data Distribution Service for Real-Time Interoperable Agricultural Machinery Communications
Inter-manufacturer plug-and-play communication in agricultural machinery is currently based on the ISO 11783 standard series, which specifies a 250 kbit/s CAN bus communication layer. To support higher-bandwidth use cases, the ISO~23870 series is being developed for next-generation Ethernet-based agricultural machine-to-machine communication. Modern Ethernet/IP-based architectures often make use of a middleware for discovery, data exchange, quality of service configuration, and security. This paper evaluates the Data Distribution Service (DDS) as a candidate middleware for secure, plug-and-play agricultural machinery networking. DDS-based proof-of-concept communication design is presented for a representative Task Controller (TC) and implement scenario, including implement-description topics and separate best-effort and reliable topics for runtime process data. Design was implemented in C++ using the FastDDS library and benchmarked on embedded hardware representative of agricultural machinery. Runtime throughput was evaluated for one-to-one and one-to-two TC-implement scenarios under four DDS security configurations. The results show that DDS security mechanisms substantially reduce maximum throughput on embedded hardware. In the tested best-effort scenarios, signing and encryption reduced mean throughput by approximately 70-84% compared with the unsecured configuration. Encrypted one-to-one best-effort case achieved approximately 4980 received process data updates per second on both the TC and implement, corresponding to about 50 process data updates per second per simulated section for 100 rate-controllable sections. These results indicate that DDS is a technically plausible middleware candidate for secure Ethernet-based agricultural machinery interoperability, while further work is required to evaluate latency, scalability, vendor interoperability, and lower-power devices.