Some Concepts about Omniverse Connectors

During the period of developing connectors of a certain DCC software, I know that I can use the c++ function of startOmniverse() in omniCLI library to establish a connection with Nucleus server.

Others like creating a live session, reading the USD file and loading, but what’s next? How to communicate with DCC software? Modifying the same USD file on Nucleus? When the USD file is edited by program, is these data temporarily stored in the Nucleus server cache? Where is the entity of the Nucleus cache? localhost cpu, memmory, or remote server cpu, memory?