TCP sessions with gRPC

Sorry if this question is naive. (gRPC novice here). But, I would like to understand this.

Let's say I have a gRPC service definition like this:

service ABC {
  // Update one or more entities.
  rpc Write(WriteRequest) returns (WriteResponse) {
  }
  // Read one or more entities.
  rpc Read(ReadRequest) returns (stream ReadResponse) 
  {
  }
  // Represents the bidirectional stream 
  rpc StreamChannel(stream StreamMessageRequest)
      returns (stream StreamMessageResponse) {
  }
}

Our potential use case would be the server built using C++ and the client using Java. (Not sure is that matters).

I would like to understand how the TCP sessions are managed. The Stream Channel would be used for constant telemetry data streaming between the client and the server. (Constant data transfer, but the bulk from the server to the client).

Does the StreamChannel have a separate TCP session, while for every Write and Read a new session would be established and terminated after the call is done?

Or is there a single TCP session over which all the communication happens?

Again, please excuse me if this is very naive.

Thanks for your time.