Transport Protocol Change in Fast DDS

[AnoopGQuest]

Can we send data from publisher side using a particular protocol like UDP and receive data from the subscriber side using another protocol like TCP?

I was running a ros2 publisher node with transport protocol selected as UDP and ros2 subscriber node with transport protocol selected as PCIe...I was not able to subscribe the message sent by the publisher. Why?

[JesusPoderoso]

Hi @AnoopGQuest, thanks for using Fast DDS.
I am afraid that is not possible using Fast DDS: the subscriber and publishers won't match. But DDS Router can fulfill your requirements (using the Fast DDS transports: SHM, UDP and/or TCP).

Although this would be the scenario using just Fast DDS...

graph LR;
    UDP_writer -. / .-> TCP_reader

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The eProsima's DDS Router can perform the communication.

graph LR;
    UDP_writer --> DDS_Router
    DDS_Router --> TCP_reader

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DDS Router allows configuring different transports on different DDS Router's participant, so your requested scenario can be addressed.

graph LR;
    UDP_writer --> UDP_participant
    TCP_participant --> TCP_reader
   subgraph DDS_Router
    UDP_participant-->TCP_participant
    end

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