DDS Explained: The Data-Centric Middleware Behind ROS2 and Distributed Real-Time Systems

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The OMG Data Distribution Service (DDS) is a standard communication technology built for scalable, reliable, real-time distributed systems. It is used across robotics, autonomous vehicles, aerospace, defense, industrial automation, and medical devices. DDS was created to overcome the limits of traditional client-server models, which become impractical when hundreds or thousands of nodes must exchange continuous data streams. It uses a data-centric publish-subscribe model in which publishers and subscribers exchange information through shared data spaces without direct links, with discovery and delivery handled automatically. DDS also serves as the underlying communication layer of ROS2.

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