NETWORK-BASED EVENT NOTIFICATION SYSTEM

PROBLEM TO BE SOLVED: To allow a user to receive a notification from a device regarding change in a job even when the user requests job processing to the device from a host and then moves to another host, and to suppress increase in a processing load on each device and host connected to a network and increase in network traffic.SOLUTION: When the type of an event is a job state, an event code includes a user ID (S20) on the one hand, and a subscription in a subscription table includes a filter element coupling an event type code and a user ID (S21) on the other hand. Regardless of the presence of the user ID, an event notification manager filters each subscription to determine whether or not the filter element matches the event code excluding a part thereof (S23), and notifies an image formation device of the event (S26A) when a match is found.