Patent ID: 8200755

Claim:
A presence administration method comprising: executing at a presence administration device: storing in a client table a first user identifier in association with identifiers of a plurality of client devices operated by the first user; storing in a buddy list, of the first user, a second user identifier and a display name for a second user named by the first user, in association with the first user identifier, where the second user identifier identifies a second user whose presence information is to be watched by the first user, and the display name corresponds to the second user identifier in the buddy list; storing in a watcher list of the first user, the first user identifier in association with the second user identifier from the buddy list; storing in a presence table presence information in association with the second user identifier; upon update of the presence information of the second user, referring to the watcher list of the first user and notifying, to the plurality of client devices for the first user in the client table, updated presence information associated with the second user identifier in the presence table; upon update of the buddy list of the first user, including when a change of the display name of the second user in the buddy list of the first user is accepted, notifying, to the plurality of client devices for the first user in the client table, updated buddy list information of the first user; storing a notified last connection time that is a time at which a client device of the first user has last communicated with the presence administration device; and acquiring updated buddy list information from the buddy list of the first user updated after the last connection time to the presence administration device, and presence information of one or more buddies which are on the buddy list updated and of which presence information has changed after the last connection time.