DDS Service Discovery implements a two-phase principle where DomainParticipants A, B, and C first discover each other via SPDP multicast on 239.255.0.1:7400, then exchange Writer and Reader endpoint information through a shared Service Discovery Table. After participant discovery, the Writer sends data directly to Reader endpoints (192.168.1.20:7410 and 192.168.1.30:7410) with no forwarding overhead, enabling low-latency peer-to-peer communication. This architecture demonstrates how DDS achieves dynamic discovery and direct data flow in distributed real-time systems, critical for mission-critical applications requiring deterministic latency and fault tolerance. Fork this diagram on Diagrams.so to customize multicast groups, add QoS policies, or model failover scenarios for your DDS deployment. The design handles dynamic readers going offline—DP-C notifies DP-A to update the discovery table—making it ideal for systems with mobile or intermittent participants.