private void send_RTSP_request(String request_type)
  {
    try{
    	//Use the RTSPBufferedWriter to write to the RTSP socket

    	//write the request line:
    	RTSPBufferedWriter.write(request_type);
  
    	//write the CSeq line: 
    	RTSPBufferedWriter.write(RTSPSeqNb);

    	//check if request_type is equal to "SETUP" and in this case write the Transport: line advertising to the server the port used to receive the RTP packets RTP_RCV_PORT
    	//otherwise, write the Session line from the RTSPid field
    	if(request_type.equals("SETUP")){
    		RTSPBufferedWriter.write(RTP_RCV_PORT);
    	}
    	else {
    		RTSPBufferedWriter.write(RTSPid);
    	}

      RTSPBufferedWriter.flush();
    }
    catch(Exception ex)
      {
	System.out.println("Exception caught: "+ex);
	System.exit(0);
      }
  }