Method and apparatus for data security and automatic repeat request implementation in a wireless communication system
A method and apparatus for implementing data security and automatic repeat request (ARQ) in a wireless communication system are disclosed. Cipher entities are included in a wireless transmit/receive unit (WTRU) and an access gateway (aGW), and outer ARQ, (or radio link control (RLC)), entities are included in the WTRU and an evolved Node-B (eNode-B). Each cipher entity is located on top of an outer ARQ entity. The cipher entities cipher and decipher a data block by using a generic sequence number (SN) assigned to the data block. The outer ARQ entities may segment the ciphered data block to multiple packet data units (PDUs), may concatenate multiple ciphered data blocks to a PDU, or may generate one PDU from one data block. The outer ARQ entities may segment or re-segment the PDU when a transmission failure occurs.
1. A wireless transmit/receive unit (WTRU) comprising:
circuitry configured to be provided a first assignment of physical resources;
the circuitry is further configured to provide a packet data convergence protocol (PDCP) sequence number (SN) to a data block;
the circuitry is further configured to cipher the data block using the PDCP SN and a bearer identification (ID);
the circuitry is further configured to produce a radio link control (RLC) protocol data unit (PDU) including at least a portion of the ciphered data block;
the circuitry is further configured to transmit the RLC PDU using the first assigned physical resources as a first long term evolution (LTE) signal;
the circuitry is further configured to be provided a second assignment of physical resources; and
the circuitry is further configured on a condition that the transmission of the RLC PDU was not successful:
to determine whether to retransmit the RLC PDU or to segment the RLC PDU into RLC PDU segments and transmit the RLC PDU segments based on the second assignment of physical resources; and
to retransmit the RLC PDU or to transmit at least one of the RLC PDU segments using the second assigned physical resources as a second LTE signal.
2. The WTRU of claim 1 wherein the RLC PDU segments include a re-segmentation identifier.
3. The WTRU of claim 1 wherein the RLC layer uses an automatic repeat request (ARQ) mechanism.
4. The WTRU of claim 3 wherein the transmission of the RLC PDU uses a hybrid automatic repeat request mechanism.
5. A method comprising:
providing, by a wireless transmit/receive unit (WTRU), a packet data convergence protocol (PDCP) sequence number (SN) to a data block;
ciphering, by the WTRU, the data block using the PDCP SN and a bearer identification (ID);
producing, by the WTRU, a radio link control (RLC) protocol data unit (PDU) including at least a portion of the ciphered data block;
transmitting, by the WTRU, the RLC PDU using first assigned physical resources as a first long term evolution (LTE) signal; and
on a condition that the transmission of the RLC PDU was not successful:
determining, by the WTRU, whether to retransmit the RLC PDU or to segment the RLC PDU into RLC PDU segments and transmit the RLC PDU segments based on a second assignment of physical resources; and
retransmitting, by the WTRU, the RLC PDU or transmitting at least one of the RLC PDU segments using the second assigned physical resources as a second LTE signal.
6. The method of claim 5 wherein the RLC PDU segments include a re-segmentation identifier.
7. The method of claim 5 wherein the RLC layer uses an automatic repeat request (ARQ) mechanism.
8. The method of claim 7 wherein the transmission of the RLC PDU uses a hybrid automatic repeat request mechanism.