Method for recovering from a received data error in a mobile communication system providing a multimedia broadcast/multicast service

1. A method for enabling a user equipment (UE) to recover from a multimedia broadcast/multicast service (MBMS) data error in a mobile communication system, the mobile communication system including a radio network controller (RNC) and at least one cell for transmitting MBMS data to at least one UE according to a control operation of the RNC, the RNC transmitting first control information to UEs located in each cell, each of the UEs receiving the first control information and the MBMS data, the method comprising the steps of:

(a) notifying the RNC that an MBMS data reception error has occurred when the error in the received MBMS data is detected;

(b) receiving response information associated with the MBMS data reception error from the RNC;

(c) determining whether control information contained in the response information matches the first control information; and

(d) recovering from the MBMS data reception error according to a result of the determination.

2. The method as set forth in claim 1 , wherein the UE notifies the RNC that the MBMS data reception error has occurred, along with a control information retransmission request.

3. The method as set forth in claim 1 , wherein the UE notifies the RNC that the MBMS data reception error has occurred, along with a UE identity (ID).

4. The method as set forth in claim 1 , wherein the UE notifies the RNC that the MBMS data reception error has occurred, along with information indicating a number of changes in the first control information.

5. The method as set forth in claim 1 , wherein the UE notifies the RNC that the MBMS data reception error has occurred, along with a service identity (ID) of the MBMS data.

6. The method as set forth in claim 1 , wherein the response information includes information indicating a number of changes in the control information.

7. The method as set forth in claim 1 , further comprising the step of:

(e) if the control information contained in the response information is different from the first control information, recovering from the MBMS data reception error using the control information included in the response information and information indicating a number of changes in the control information.

8. The method as set forth in claim 1 , further comprising the step of:

(e) if the control information contained in the response information matches the first control information, not notifying the RNC of the MBMS data reception error during a preset time.

9. A method for enabling a radio network controller (RNC) to perform a control operation so that a multimedia broadcast/multicast service (MBMS) data error occurring in a user equipment (UE) can be recovered from in a mobile communication system, the mobile communication system including the RNC and at least one cell for transmitting MBMS data to at least one UE according to a control operation of the RNC, the RNC transmitting control information to UEs located in each cell, each of the UEs receiving the control information and the MBMS data, the method comprising the steps of:

(a) receiving, from the UE, an MBMS data reception error notification indicating that an MBMS data reception error has occurred; and

(b) transmitting, from the RNC, a control signal currently used therein to the UE in response to the MBMS data reception error notification, if the RNC recognizes whether the transmitted control information to the UE does not match control information in the RNC; and

(c) transmitting, from the RNC, information indicating a cause of the MBMS data reception error to the UE, in response to the MBMS data reception error notification, if the RNC recognizes whether the transmitted control information to the UE matches control information in the RNC.

10. The method as set forth in claim 9 , wherein the UE transmits the MBMS data reception error notification to the RNC, along with a control information retransmission request.

11. The method as set forth in claim 9 , wherein the UE transmits the MBMS data reception error notification to the RNC, along with information indicating a number of changes in control information currently used therein.

12. The method as set forth in claim 9 , wherein the control signal includes the control information currently used in the RNC and information indicating a number of changes in the control information.

13. The method as set forth in claim 12 , wherein the RNC transmits, to the UE, the control information currently used therein and the information indicating the number of changes in the control information, if information indicating a number of changes in control information included in the MBMS data reception error notification is different from the number of changes in the control information currently used in the RNC.

14. The method as set forth in claim 12 , wherein the RNC transmits, to the UE, the information indicating the number of changes in the control information, if control information included in the MBMS data reception error notification matches the control information currently used in the RNC.

15. A method for enabling a user equipment (UE) to recover from an error in multimedia broadcast/multicast service (MBMS) data in a mobile communication system, the mobile communication system including a plurality of UEs, a plurality of cells in which the plurality of UEs are located, a radio network controller (RNC) for providing MBMS to the cells and a core network (CN) for transmitting the MBMS data, the method comprising the steps of:

(a) receiving, by the RNC, an MBMS data reception error notification message from the UE;

(b) reading a number of changes in control information based upon MBMS data reception;

(c) determining whether the number of changes in MBMS control information stored in the RNC matches the read number of changes; and

(d) if the number of changes in the MBMS control information stored in the RNC is different from the read number of changes, transmitting a control signal including changed MBMS control information and information indicating a change of the MBMS control information to the UE.

16. The method as set forth in claim 15 , further comprising the step of:

(e) if the number of changes in the MBMS control information stored in the RNC matches the read number of changes, transmitting a control signal containing only the information indicating the change of the MBMS control information contained in the RNC to the UE.

17. The method as set forth in claim 15 , wherein the information indicating the change of the MBMS control information is a version number indicating the number of changes in the control information.

18. A method for enabling a user equipment (UE) to recover from an error in multimedia broadcast/multicast service (MBMS) data in a mobile communication system, the mobile communication system including a plurality of UEs, a plurality of cells in which the plurality of UEs are located, a radio network controller (RNC) for providing MBMS to the plurality of cells and a core network (CN) for transmitting the MBMS data, the method comprising the steps of:

(a) receiving, by the CN, an MBMS data reception error notification message from the UE;

(b) reading a number of changes in control information based upon MBMS data reception;

(c) determining whether a number of changes in MBMS control information stored in the CN matches the read number of changes; and

(d) if the number of changes of the MBMS control information stored in the CN is different from the read number of changes, transmitting a control signal including changed MBMS control information and information indicating a change of the MBMS control information to the UE.

19. The method as set forth in claim 18 , wherein the MBMS control information changes an encryption key based upon the MBMS data reception.