Reference Architecture for VDA5050

The German Association of the Automotive Industry (VDA) has recently published a specification to define the communication between autonomous guided vehicles (AGV) and SCADA control systems. The new specification called VDA 5050 sets MQTT as the standard protocol and defines the subject namespace and the user data format for each message type defined in the specification. The aim is to enable companies such as Audi, Daimler, Ford, etc. to use AGVs from different manufacturers, all of which communicate with a single SCADA system.

At HiveMQ, we consider the use of MQTT as the standard for message transmission between AGV and SCADA systems to be absolutely sensible. MQTT offers a simple, lightweight protocol that enables reliable and scalable implementations. For these reasons, more and more companies are using MQTT in manufacturing and logistics.

The VDA 5050 defines the MQTT message formats, among other things, but does not explain how to implement a system that uses the specification. For this reason, we decided to define a reference architecture approach for VDA 5050 implementations. Our article describes which features must be available for the key component, the MQTT message broker. Functions such as performance, cluster capability, reliability of the MQTT broker as well as the support of all functions of the MQTT protocol (versions 3 and 5) are presented in detail. We discuss the security setup for the clients and for the broker and secure the communication between them, as well as the connection of external central authentication systems. The document also includes an approach to the MQTT client setups, as well as the topic structure used in one of the most important use cases, the order-state communication scenario.

We hope this is a valuable resource for vendors and customers considering using VDA 5050 for their AGV implementations.

Please let us know if you have any questions or feedback.