Method for resetting MAC layer entity in a W-CDMA communication system using HSDPA

1. A method for resetting a buffer for retransmission of a MAC (Medium Access Control) layer entity to prevent the MAC layer entity from performing unnecessary transmission upon occurrence of an unrecoverable error in an RLC (Radio Link Control) layer entity in a communication system, the method comprising the step of:

detecting the occurrence of the error by the RLC (Radio Link Control) layer entity;

requesting reset of the buffer of the MAC layer entity based on the detected error; and

discarding the data of the buffer of the MAC layer entity in response to the requested reset.

2. A method for resetting a first buffer for retransmission of a MAC (Medium Access Control) layer entity to prevent the MAC layer entity from performing unnecessary transmission upon occurrence of an unrecoverable error in an RLC (Radio Link Control) layer entity in a communication system, the method comprising the step of:

detecting the occurrence of the error by the RLC (Radio Link Control) layer entity;

requesting reset of the first buffer of the MAC layer entity based on the detected error;

discarding the data of the first buffer of the MAC layer entity in response to the requested reset; and

requesting reset of a second buffer of a counterpart MAC layer entity.

3. A method for resetting a MAC-hs (Medium Access Control-high speed) layer entity to prevent the MAC-hs layer entity from performing unnecessary transmission/retransmission upon occurrence of an unrecoverable error in an RLC (Radio Link Control) layer entity in a communication system using HSDPA (High Speed Downlink Packet Access), the system including (1) an RNC (Radio Network Controller) having (i) the RLC layer entity for distinguishing packet data, (ii) a MAC-d (MAC-dedicated) layer entity for multiplexing the distinguished packet data from the RLC layer entity to corresponding dedicated channels, and (iii) a MAC-c/sh (MAC-common/shared) layer entity for multiplexing the distinguished packet data to corresponding common channels, and (2) a Node B having the MAC-hs layer entity for transmitting and retransmitting the multiplexed packet data to a user equipmen (UE) at high speed, wherein the multiplexed packet data is transmitted from the Node B to the UE over a corresponding channel, the method comprising the steps of:

resetting the RLC layer entity upon occurrence of the error; and

transmitting RLC layer entity reset information indicating reset of the RLC layer entity to the MAC-hs layer entity, and resetting the MAC-hs layer entity based on the RLC entity reset information.

4. The method as claimed in claim 3 , wherein the RLC layer entity reset information is transmitted through a primitive between the RLC layer entity and one of the MAC-d and the MAC-c/sh layer entity.

5. The method as claimed in claim 3 , wherein the RLC layer entity reset information is transmitted through a frame of a frame protocol.

6. The method as claimed in claim 3 , further comprising the step of transmitting reset information from the RLC layer entity to a counterpart RLC layer entity after a lapse of a predetermined time after transmitting the RLC layer entity reset information to the MAC-hs layer entity.

7. The method as claimed in claim 6 , wherein the predetermined time is set by considering a propagation delay time required in transmitting the RLC layer entity reset information.

8. The method as claimed in claim 6 , wherein the RLC layer entity transmits the RLC layer entity reset information to the counterpart RLC layer entity over a dedicated channel.

9. The method as claimed in claim 6 , wherein the RLC layer entity transmits a protocol data unit (PDU) indicating the RLC layer entity reset information to the counterpart RLC layer entity along with a new flag.

10. A method for resetting a MAC-hs (Medium Access Control-high speed) layer entity to prevent the MAC-hs layer entity from performing unnecessary transmissionlretransmission upon occurrence of an unrecoverable error in an RLC (Radio Link Control) layer entity in a communication system using HSDPA (High Speed Dowulink Packet Access), the system including (1) an RNC (Radio Network Controller) having (i) the RLC layer entity for distinguishing packet data, (ii) a MAC-d (MAC-dedicated) layer entity for multiplexing the distinguished packet data from the RLC layer entity to corresponding dedicated channels, and (iii) a MAC-c/sh (MAC-common/shared) layer entity for multiplexing the distinguished packet data to corresponding common channels, and (2) a Node B having the MAC-hs layer entity for transmitting and retransmitting the multiplexed packet data to a user equipment (UE) at high speed, wherein the multiplexed packet data is transmitted from the Node B to the UE over a corresponding channel, the method comprising the steps of:

resetting the RLC layer entity upon occurrence of the error;

transmitting RLC layer entity reset information indicating reset of the RLC layer entity to the MAC-hs layer entity; and

resetting the MAC-hs layer entity based on the RLC layer entity reset information, and transmitting MAC-hs layer entity reset information indicating reset of the MAC-hs layer entity from the MAC-hs layer entity to a counterpart MAC-hs layer entity.

11. The method as claimed in claim 10 , wherein the MAC-hs entity reset information is transmitted through a MAC signaling message.

12. The method as claimed in claim 11 , wherein the MAC signaling message includes (i) a header having a signaling indication indicating that the MAC signaling message includes only MAC layer entity reset information, and (ii) a reset indication indicating reset based on the MAC-hs layer entity reset information.

13. The method as claimed in claim 10 , further comprising the step of transmitting the RLC layer entity reset information from the RLC layer entity to the counterpart RLC layer entity after a lapse of a predetermined time after transmitting the RLC layer entity reset information to the MAC-hs layer entity.

14. The method as claimed in claim 13 , wherein the predetermined time is set by considering a propagation delay time required in transmitting the RLC layer entity reset information.

15. The method as claimed in claim 13 , wherein the RLC layer entity transmits the RLC layer entity reset information to the counterpart RLC layer entity over a dedicated channel.

16. The method as claimed in claim 13 , wherein the RLC layer entity transmits a protocol data unit (PDU) indicating the RLC layer entity reset information to the counterpart RLC layer entity along with a new flag.