Data push service system and method using a heterogeneous network

1. A system for transmitting push data to a Hybrid Access Terminal (HAT) which can be connected to a circuit network or a packet network, and is registered in a new access network determined by an access network switching operation in a heterogeneous mobile communication system in which at least one circuit network is overlapped with at least one packet network, the system comprising:

a Packet Service & Mobility Gateway (PSMG) for acquiring access state and connection information of the HAT from the circuit network and the packet network, and generating an access network switching request of the HAT upon receipt of an external request signal; and

a Push Proxy Gateway (PPG) for acquiring access information of the HAT which will transmit the push data from the PSMG, and transmitting a request message to the PSMG such that the HAT can access a network selected by the push data.

2. The system according to claim 1 , wherein the PPG transmits the push data to the HAT over the selected network.

3. The system according to claim 1 , further comprising:

a Push Initiator (PI) for generating push data to be transmitted to a specific HAT, and controlling the PPG to transmit the generated push data to the specific HAT.

4. The system according to claim 3 , wherein the PI receives selected network information corresponding to the push data from the PPG, and transmits the push data to the specific HAT over the selected network.

5. The system according to claim 1 , wherein the PPG determines whether the HAT which will transmit the push data can receive a push service, and transmits the push data according to the determination result.

6. The system according to claim 1 , wherein the PPG operates a timer upon receipt of the access network switching request of the HAT, and transmits the push data when receiving connection information of a corresponding HAT before the timer expires.

7. The system according to claim 1 , wherein the PSMG transmits a packet network switching access request to a corresponding HAT when the selected network is equal to the packet network, the corresponding HAT is in a voice communication mode, and the voice communication mode is finished.

8. A method for transmitting push data to a Hybrid Access Terminal (HAT) which can be connected to a circuit network or a packet network, and registers access state and connection information in a new access network determined by an access network switching operation in a heterogeneous mobile communication system in which at least one circuit network is overlapped with at least one packet network, comprising the steps of:

requesting, by a Push Proxy Gateway (PPG), access state and connection information of the HAT to which the push data is to be transmitted, from a Packet Service & Mobility Gateway (PSMG), when the push data is generated;

detecting, by the PSMG, the requested access state and connection information of the HAT, and transmitting the detected information to the PPG; and

generating, by the PPG, a request signal when a corresponding HAT is not connected to a selected network corresponding to push data characteristics such that the HAT is switched to the selected network over the PSMG.

9. The method according to claim 8 , further comprising the steps of:

acquiring, by the PSMG, connection information of the HAT switched to the selected network, and transmitting the acquired information to the PPG; and

transmitting, by the PPG, the push data to the corresponding HAT using the connection information.

10. The method according to claim 8 , further comprising the step of:

determining, by the PPG, whether the HAT which will transmit the push data can receive a push service, and transmitting the push data according to the determination result.

11. The method according to claim 8 , further comprising the step of:

transmitting, by the PPG, the push data, if the PPG receives the connection information of the corresponding HAT from the PSMG within a predetermined period of time upon receipt of an access network switching request signal of the HAT.

12. The method according to claim 8 , further comprising the step of:

determining, by the PSMG, whether a voice communication mode of the HAT is finished if the selected network is equal to a circuit network and the corresponding HAT is in the voice communication mode, and transmitting a switching access request to the corresponding HAT.