Skip to content

Paper

Dependency Chain Analysis of ROS 2 DDS QoS Policies:
From Lifecycle Tutorial to Static Validation

Sanghoon Lee, Junha Kang, and Kyung-Joon Park

Abstract

ROS 2 relies on the Data Distribution Service (DDS), which offers more than 20 Quality-of-Service (QoS) policies governing availability, reliability, and resource utilization. Yet ROS 2 users lack clear guidance on safe policy combinations and validation processes prior to deployment, which often leads to trial-and-error tuning and unexpected runtime failures. To address these challenges, we analyze DDS publisher-subscriber communication over a lifecycle divided into Discovery, Data Exchange, and Disassociation, and provide a user-oriented tutorial explaining how 16 QoS policies operate across these phases. We derive a QoS Policy Chain that encodes inter-policy relationships as 40 dependency-violation rules grounded in the OMG DDS standard, open-source implementations, and empirical measurements. Finally, we introduce QoS Guard, a ROS 2 tool that statically extracts endpoint QoS settings from a package, validates them offline, flags conflicts, and enables pre-deployment risk detection without establishing a live ROS 2 session. Together, these contributions give ROS 2 users both conceptual insight and a concrete tool that enables early detection of misconfigurations, improving the reliability and resource efficiency of ROS 2-based robotic systems.

  • Home: QoS Guard overview and usage
  • QoS Encyclopedia: definitions and lifecycle roles of DDS QoS policies
  • Dependency Map: interactive dependency graph and relationship overview
  • Rules & Evidence: the 40 rules with Fast DDS and Cyclone DDS verification, each linked to its evidence page