Patent ID: 7551596

Claim:
A method for transmitting control information for an uplink packet data service in a mobile communication system, the method comprising the steps of: forming a first protocol data unit (PDU) including uplink packet data; forming a control service data unit (SDU) including control information for an uplink packet data service; forming at least one first header part corresponding to the first PDU by using a data description indicator (DDI) field representing the first PDU and an N field representing the number of uplink packet data included in the first PDU; forming a second header part corresponding to the control SDU by using a DDI field set as a predetermined specific value representing that the control SDU is transmitted; and forming a second data packet unit (PDU) by concatenating a header and a payload, and transmitting the second PDU to a Node B, wherein the header includes the header parts, and the payload includes the first PDU and the control SDU.