This QosPolicy specifies the priority with which the Data Distribution System can handle the data produced by the DataWriter.

Attributes

Value	Meaning	Concerns	RxO	Changeable
A long: value	This policy is a hint to the infrastructure as to how to set the priority of the underlying transport used to send the data. The default value of the transport_priority is zero.	Topic, DataWriter	N/A	Yes

The purpose of this QoS is to allow the application to take advantage of transports capable of sending messages with different priorities. This policy is considered a hint. The policy depends on the ability of the underlying transports to set a priority on the messages they send. Any value within the range of a 32-bit signed integer may be chosen; higher values indicate higher priority. However, any further interpretation of this policy is specific to a particular transport and a particular implementation of the Service.It is expected that during transport configuration the application would provide a mapping between the values of the TRANSPORT_PRIORITY set on DataWriter and the values meaningful to each transport. This mapping would then be used by the infrastructure when propagating the data written by the DataWriter.