return to the Quality of Service (QoS) Parameters

The TOPIC_DATA QoS allows the application to attach additional information to the created Topic such that when a remote application discovers their existence it can examine the information and use it in an application-defined way. In combination with the listeners on the DataReader and DataWriter as well as by means of operations such as ignore_topic, these QoS can assist an application to extend the provided QoS.

Source: DDS 1.4 Spec