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Data Distribution Service (DDS) is middleware that lets distributed applications publish and subscribe to typed data through named topics. It is designed for real-time and embedded systems, with configurable Quality of Service (QoS) policies for requirements such as reliability, delivery deadlines, bandwidth, and resource limits. Robotics, including ROS 2 communication, is one concrete application; whether DDS fits a system depends on its needs and deployment.
What is DDS?
DDS is an open international standard managed by the Object Management Group (OMG). It sits between application software and lower-level operating-system, network-transport, and data-format details. Rather than treating communication only as messages placed on a queue, DDS uses a data-centric model: applications work with data objects identified by topic names and, where applicable, keys. The middleware manages discovery and distribution among publishers and subscribers according to configured policies. OMG’s DDS overview describes the standard and its intended role in real-time and embedded systems.
How DDS works in an application
Publishers and subscribers share typed data
An application component publishes data on a named topic; another component subscribes to that topic to receive relevant updates. Components can be distributed across processes or machines without each publisher needing to know the precise location of every subscriber. DDS implementations handle participant discovery and data distribution, while application code defines the data and topics it uses.
QoS expresses communication requirements
Quality of Service policies let a deployment configure aspects such as reliability, bandwidth behavior, delivery deadlines, and resource limits. These are controls, not automatic guarantees: meeting a deadline or reliability target depends on the chosen policies and on the implementation, topology, traffic, network, and other configuration. The DDS Foundation’s introduction also explains DDS as data-centric middleware for distributed connectivity.
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Where DDS is used
Robotics and ROS 2
DDS can provide communication between ROS 2 nodes, including nodes running on different robots. The Eclipse Foundation identifies Eclipse Cyclone DDS as a DDS implementation used for ROS 2 communication. This is an example of an implementation in an ecosystem, not evidence that every ROS 2 distribution or deployment uses the same middleware or configuration. Check the support information for the ROS 2 distribution and deployment you plan to use. Eclipse Cyclone DDS at the Eclipse Foundation
Real-time distributed systems
DDS is intended for distributed systems where applications need structured data exchange and configurable communication behavior. RTI describes uses in mission- and safety-critical systems, including military avionics; that characterization is RTI’s description of applications, not a claim that every DDS product or deployment is safety-certified. RTI’s DDS product information
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Embedded and IoT systems
OMG and the DDS Foundation position DDS for real-time and embedded systems, as well as business- or mission-critical IoT connectivity. These are target areas, not a recommendation to use DDS for every connected device: the application’s communication needs and operational constraints should determine the design.
Why choose DDS—and what to evaluate
DDS may suit systems whose components need to exchange typed data without being tightly coupled to one another’s locations, and whose communication behavior needs configurable policies. Before choosing DDS or a particular implementation, assess the deployment rather than relying on the standard’s intended capabilities alone:
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- QoS needs: Identify the required reliability behavior, deadlines, bandwidth constraints, and resource limits, then determine whether the implementation and configuration can support them in the actual environment.
- Interoperability: If components from different implementations must communicate, verify the relevant protocol, version, and feature compatibility. OMG catalogs DDSI-RTPS as a related interoperability specification; a catalog entry alone does not establish compatibility between specific products or versions. OMG’s DDS specifications catalog
- Application ecosystem: For ROS 2, confirm support for the implementation in the chosen ROS 2 distribution and deployment. The existence of Cyclone DDS and RTI ROS 2 materials is not a complete compatibility matrix.
- Operational fit: Evaluate discovery behavior, network configuration, security, platform support, observability, vendor support, and licensing for the particular system. These details vary by implementation and are not settled by the DDS standard alone.
DDS is a standard, not one product
The DDS standard and a DDS implementation are not the same thing. OMG defines specifications; vendors and open-source projects provide implementations with their own platform support, features, operational guidance, and licensing. OMG’s specifications catalog lists DDSI-RTPS 2.3 as formal in May 2019, which is a dated catalog entry rather than confirmation that 2.3 is the newest version. Consult the catalog and implementation documentation for the versions and features relevant to a deployment. No single implementation or quantitative performance winner follows from the standard itself.
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