6.4.1.1 Quality of service parameters

6.4.1.1.1 QosCategory and DatagramQos

The QosDataTypes defined in the following chapters are used in the DatagramQos parameter in different datagram specific transport protocol mapping settings.

The DatagramQos contains an array of QosDataTypes. The array is null or empty if no QoS related parameters are set.

The DatagramQos parameter is always combined with a QosCategory parameter. Depending on the content of the QosCategory String, different elements need to be present within the DatagramQos array.

The specific processing of the QosCategory and DatagramQos content is described in 5.4.6.4.

Standard QosCategory values are defined in Table 118.

6.4.1.1.2 QosDataType structure

This Structure DataType is an abstract base type for Structures with QoS related parameters. The QosDataType is formally defined in Table 119.

The QosDataType Structure representation in the AddressSpace is defined in Table 120.

6.4.1.1.3 TransmitQosDataType

This Structure DataType is an abstract base type for Structures with transmit QoS related parameters. The TransmitQosDataType is formally defined in Table 121.

The TransmitQosDataType Structure representation in the AddressSpace is defined in Table 122.

6.4.1.1.4 TransmitQosPriorityDataType

6.4.1.1.4.1 PriorityLabel

The PriorityLabel with DataType String specifies the priority of the according sender. The network stack will use the PriorityLabel to look up the priority settings for the transport protocol headers.

The priority labels defined by OPC UA should have the following form:

opc.qos.lbl://<label>

Example values are “opc.qos.lbl://low” or “opc.qos.lbl://high”. The mapping is described in 5.4.6.4.

Note: This version does not define concrete labels. The engineering process needs to provide them and also build up the PriorityMappingTable in OPC 10000-22 accordingly.

6.4.1.1.4.2 TransmitQosPriorityDataType structure

This Structure DataType is used to represent the priority lable specific transmit QoS parameters. It is a subtype of the TransmitQosDataType defined in 6.4.1.1.3.

The TransmitQosPriorityDataType is formally defined in Table 123.

Its representation in the AddressSpace is defined in Table 124.

6.4.1.1.5 ReceiveQosDataType

This Structure DataType is an abstract base type for Structures with receive QoS related parameters. The ReceiveQosDataType is formally defined in Table 125.

The ReceiveQosDataType Structure representation in the AddressSpace is defined in Table 126.

6.4.1.1.6 ReceiveQosPriorityDataType

6.4.1.1.6.1 PriorityLabel

The PriorityLabel with DataType String specifies the priority of the according sender.

Futher details are defined in 6.4.1.1.4.1.

6.4.1.1.6.2 ReceiveQosPriorityDataType structure

This Structure DataType is used to represent the priority lable specific receive QoS parameters. It is a subtype of the ReceiveQosDataType defined in 6.4.1.1.5.

The ReceiveQosPriorityDataType is formally defined in Table 127.

Its representation in the AddressSpace is defined in Table 128.