Abstract: Provided is a method and apparatus for providing a multimedia message service based on a Parlay X Web service to easily check the status of a multimedia message which is requested to be transmitted in a multimedia messaging application server. The apparatus activates a delivery status informing function for each application server upon receipt of a delivery status information activation request, receives a process result for the multimedia message requested by the application server from an MMS server, and transmits the delivery status information for the requested multimedia message to the application server, for which the status informing function is activated, through a status informing message in real-time.

Abstract: The present invention provides a method and system for providing a SIP based Instance Messaging (IM), and an IM proxy server therefor. An IM proxy server for performing a proxy function in a mobile communication network is configured to provide an IM service between a mobile terminal lacking an SIP function and an IM server. Further, the IM proxy server converts an IM message received from the mobile terminal into a corresponding SIP message mapped thereto, transmits the SIP message to the IM server through a call session control server, converts an SIP message received from the IM server through the call session control server into an IM message recognizable by the mobile terminal, and transmits the IM message to the mobile terminal, thus providing the SIP based IM service to the mobile terminal lacking an SIP function.

Abstract: The present invention relates to a method of balancing a load and method of setting up a call using the load balancing method in a General Packet Radio Service (GPRS) network, which prevents a load from concentrating on a specific Gateway GPRS Supporting Node (GGSN) in the GPRS network, thus reducing a probability of failure in session establishment due to increased traffic. In the load balancing method, when a Service GPRS Supporting Node (SGSN) connected to a mobile node establishes a session, it selects a GGSN having a smallest number of established sessions among a plurality of GGSNs corresponding to an Access Point Name (APN) included in an Activate PDP Context Request message received from the mobile node and requests the selected GGSN to establish a session, thus solving a problem in which a load concentrates on a specific GGSN.