A process and system are described in which a session is established between a client application and a communication relay program being executed by a processor. In response to a process request from the client application, session information is added to the process request to identify the established session. Next, the process request with the session information is transmitted to an image processing apparatus. Responses received from the image processing apparatus may include the session information to identify to which session each response belongs. The communication relay program removes the session information from the response and forwards the response to the client application through the relevant session.