In response to a print request from a host computer, a port for receiving print data is assigned to the host computer, the host computer is notified of a URI representing the port that serves as a destination of print data, and the port is associated with the URI in a port-status management table. When a connection for sending print data from a host computer is established, the port-status management table is referred to. If the host computer is associated with the port of the connection, printing is executed. After receiving print data, the port is closed, and the port-status management table is updated to cancel the assignment of the port to the host computer.