General queries in MicroXRCE DDS working

[Muthulakshimi]

1. Whys session required in microxrcedds and not used in dds
2. How to get the throughput tested for the hello world program of the microxrce dds cuz when i add in the throughput code the delay in connected = uxr_run_session_time(&session, 1000); line of code is messing with the throughput results.
3. As the DDS follows the queue to send and receive the data via dds_take(so eventually the history cache is sequentially getting erased) whats happening with microxrce dds
4. Whts the max payload size of microxrce dds and how do i test it out
5. Whats the role of agent and hows it serving a different purpose from the servers
6. Why cant cyclone dds be used for resource constrained env (please dont give the features of microxrcedds i want to know how it differs in the functioning pov)
7. how is the reliability maintained in the case of microxrcedds just like dds uses qos

In general could you please give me a generic picture (with diagram) on how data is being sent via publisher/subscriber communication.