rmw_dds_common Features
This package includes:
- A generic to track DDS entities such as participants and data readers and writers, plus ROS nodes as an additional abstraction for any DDS based - rmwimplementation to use
- Common messages to communicate ROS nodes discovery information: 
- Some useful data types and utilities: - A generic type to withhold most state needed to implement ROS nodes discovery 
- Comparison utilities and some C++ operator overloads for - rmw_gid_tinstances
- Conversion utilities between - rmw_dds_common/msg/Gidmessages and- rmw_gid_tinstances
- A function for checking the compatibility of two QoS profiles,