Abstract: A mobile communication system and method for exchanging packet data between a host mobile communication terminal and at least one client mobile communication terminal. The host mobile communication terminal sends an SMS message including a list of data to be provided and an IP address for packet data communication. At least one client mobile communication terminal sends a list of data requested to be sent for downloading and authentication information to the host mobile communication terminal over PPP channels set up for the packet data communication. The host mobile communication terminal then sends the data requested by the client mobile communication terminal thereto over the PPP channels. Therefore, data can be exchanged between the host mobile communication terminal and the client mobile communication terminal, without using a separate physical device or means for data exchange.

Abstract: In a mobile communication system, a host mobile communication terminal transmits an invite message to a client mobile communication terminal by means of a short message, and the host mobile communication terminal and the client mobile communication terminal perform a mutual messenger service through a PDSN, such that a system for the messenger service may be easily constructed and a message may be quickly transmitted. Further, a host mobile communication terminal and client mobile communication terminals each perform a point-to-point protocol connection with a PDSN, and perform a mutual messenger service, such that they can exchange data having various formats, such as text messages, audio information, and data/image information stored in the terminal with each other.

Abstract: A presence information delivery apparatus and method for use in a mobile communication network using a short message service (SMS) is provided. An information transmission method for a mobile handset includes generating presence information file; generating a presence information message containing the presence information file; and transmitting the presence information message to at least one member of a predetermined user group using a short message service. The presence information delivery apparatus and method of the present invention are advantageous since the members without engagement of an additional presence server can share the presence information of members of a specific group.

Abstract: In a mobile communication system, a host mobile communication terminal transmits an invite message to a client mobile communication terminal by means of a short message, and the host mobile communication terminal and the client mobile communication terminal perform a mutual messenger service through a PDSN, such that a system for the messenger service may be easily constructed and a message may be quickly transmitted. Further, a host mobile communication terminal and client mobile communication terminals each perform a point-to-point protocol connection with a PDSN, and perform a mutual messenger service, such that they can exchange data having various formats, such as text messages, audio information, and data/image information stored in the terminal with each other.

Abstract: A mobile communication system and method for exchanging packet data between a host mobile communication terminal and at least one client mobile communication terminal. The host mobile communication terminal sends an SMS message including a list of data to be provided and an IP address for packet data communication. At least one client mobile communication terminal sends a list of data requested to be sent for downloading and authentication information to the host mobile communication terminal over PPP channels set up for the packet data communication. The host mobile communication terminal then sends the data requested by the client mobile communication terminal thereto over the PPP channels. Therefore, data can be exchanged between the host mobile communication terminal and the client mobile communication terminal, without using a separate physical device or means for data exchange.