Patent ID: 8145257

Claim:
An apparatus for providing mobile instant messaging service, which provides a telephone number-based mobile instant messaging service in an IMS (IP Multimedia Subsystem) domain of a mobile communication network, the apparatus comprising: a buddy status managing unit for recording and managing a status information of at least one mobile messenger subscriber; a buddy list managing unit cooperating with the buddy status managing unit for managing a buddy list of the mobile messenger subscriber based on a telephone number and providing the buddy list to the mobile messenger subscriber; a chatting service unit for providing a chatting service between the mobile messenger subscriber and a buddy selected by the mobile messenger subscriber in the buddy list provided to the mobile messenger subscriber by the buddy list managing unit; a file transmitting and receiving unit for transmitting and receiving a file between the mobile messenger subscriber and the buddy selected by the mobile messenger subscriber in the buddy list provided to the mobile messenger subscriber by the buddy list managing unit; and a cooperating unit for cooperating with a plurality of wired Internet-based instant messenger servers, wherein the buddy list managing unit receives and stores each buddy list information registered by the mobile messenger subscriber from a plurality of the wired Internet-based instant messenger servers, inserts an identifier for identifying a messenger kind of the corresponding buddy list into each buddy list information, and provides the buddy list information having the identifier to the mobile messenger subscriber.