DDS messages between multiple master in different subnets

edit

Hi, i am preparing a multi-robot environment with a set of mobile units and with one coordinating "mastermind" backend unit.

• The set of mobile robots are all with the same software and thus the same topics.
• Each Robot should be able to send a broadcast to all the others
• Each Robot should be able to send messages that is only sent to the backend

I read a lot about DDS, looked at the ros ZMQ option and even considered the ros2_socket_bridge. Obviously I would love to do this with the intended middleware DDS.

So could someone with more understanding of the inner mechanics help me with a few points

1. Is it correct that DDS does only work within the same subnet (192.168.0.1/24 255.255.255.0) and not between (192.168.0.1 -> 192.168.2.1)?
2. Is there a possibility to define a DDS Publisher profile that has a predefined receiver (like in my case the backend)

If the answer to any of these is no, is there a suggestion for another package that can do this? Thanks a lot in advance for the help!!