Patent ID: 8155053

Claim:
A method, implemented by a wireless transmit/receive unit (WTRU) for implementing data security and automatic repeat request (ARQ), the method comprising: assigning a generic sequence number (SN) to a data block in a layer above a radio link control (RLC) layer; ciphering the data block using the SN in the layer above the RLC layer; generating at least one protocol data unit (PDU) from the ciphered data block, wherein the generating the at least one PDU includes at least one of segmenting or concatenating the ciphered data block; assigning an ARQ SN to the at least one PDU; transmitting the at least one PDU to an evolved Node B (eNB); receiving, from an ARQ function in the eNB, a negative acknowledgment (NACK); transmitting an ARQ retransmission of the at least one PDU to the eNB; re-segmenting one of the ciphered data block or the PDUs to multiple sub-level PDUs in smaller size than previous PDUs when transmission of at least one previous PDU fails; including a segmentation identifier; and retransmitting the multiple PDUs.