Transport Use Cases

Working with pluggable transports.

Working with pluggable transports.

Changing the automatically registered built-in transports

• The com.rti.dds.infrastructure.TransportBuiltinKind.MASK_DEFAULT specifies the transport plugins that will be automatically registered with a newly created com.rti.dds.domain.DomainParticipant by default.
• This default can be changed by changing the value of the value of TRANSPORT_BUILTIN Qos Policy on the com.rti.dds.domain.DomainParticipant
• To change the com.rti.dds.domain.DomainParticipantQos.transport_builtin Qos Policy:

   
          DomainParticipantQos participant_qos = new DomainParticipantQos();
          
          factory.get_default_participant_qos(participant_qos);
          
          participant_qos.transport_builtin.mask = TransportBuiltinKind.SHMEM | 
                                                   TransportBuiltinKind.UDPv4;

Changing the properties of the automatically registered builtin transports

The behavior of the automatically registered builtin transports can be altered by changing their properties.

• Tell the com.rti.dds.domain.DomainParticipantFactory to create the participants disabled, as described in Turning off auto-enable of newly created participant(s)
• Get the property of the desired builtin transport plugin, say com.rti.ndds.transport.UDPv4Transport

   
          UDPv4Transport.Property_t property = new UDPv4Transport.Property_t();
                      
          TransportSupport.get_builtin_transport_property(participant, property);    

• Change the property fields as desired. Note that the properties should be changed carefully, as inappropriate values may prevent communications. For example, the com.rti.ndds.transport.UDPv4Transport properties can be changed to support large messages (assuming the underlying operating system's UDPv4 stack supports the large message size). Note: if message_size_max is increased from the default for any of the built-in transports, then the DDS_ReceiverPoolQosPolicy::buffer_size on the DomainParticipant should also be changed.

   
          /* Decrease the UDPv4 maximum message size to 64K (small messages). */
          property.message_size_max        =  9216; 
          property.recv_socket_buffer_size =  9216;
          property.send_socket_buffer_size =  9216;            

• Set the property of the desired builtin transport plugin, say com.rti.ndds.transport.UDPv4Transport

   
          TransportSupport.set_builtin_transport_property(participant, property);    

• Enable the participant to turn on communications with other participants in the domain using the new properties for the automatically registered builtin transport plugins.