Radio communication system and method having a radio link control layer
View Patent ↗Disclosed are a radio link control (RLC) entity and a data processing method for the RLC entity. The RLC entity includes a transmission data storing module that stores PDUs corresponding to SDUs transmitted from a first upper layer and outputs the stored PDUs by SDU units, a ciphering module that ciphers the PDUs stored in the transmission data storing module and transmitting the ciphered PDUs to a first RLC entity, a deciphering module that deciphers the ciphered PDUs transmitted from a second RLC entity, and a received data storing module that stores the deciphered PDUs and outputs the PDUs toward a second upper layer in the form of SDU units.
1. A transmitting device for use in a radio communication system, the transmitting device having a radio link control (RLC) layer comprising an unacknowledged mode (UM) RLC entity, the UM RLC entity comprising:
a transmission buffer that stores RLC service data units (SDUs) received from an upper layer through an unacknowledged mode-service access point (UM-SAP);
a segmentation and concatenation module that at least segments or concatenates the stored RLC SDUs to form at least one RLC protocol data unit (PDU); a header adding module that adds at least one header to the at least one RLC PDU, each of the at least one header comprising a sequence number (SN) of each of the at least one RLC PDU; and
a ciphering module that ciphers the at least one RLC PDU output from the header adding module and transmits the ciphered at least one RLC PDU to a lower layer through at least one of a plurality of channels for transmission, wherein the ciphering is performed as a final data processing step in the UM RLC entity.
2. The transmitting device of claim 1 , wherein—
the at least one RLC PDU includes the at least one header and data; and the at one least header further includes an optional length indicator.
3. The transmitting device of claim 1 , wherein the SN is excluded from the ciphering by the ciphering module.
4. The transmitting device of claim 1 , wherein the ciphered at least one RLC PDU is transmitted to an RLC entity of the radio communication system corresponding to a receiving side and at least one of the plurality of channels is DTCH, DCCH, CCCH, SHCCH, or CTCH.
5. A method for data processing at a radio link control (RLC) layer which comprises an unacknowledged mode (UM) RLC entity in a radio communication system, the method comprising:
storing RLC service data units (SDUs) received from an upper layer through an unacknowledged mode-service access point (UM-SAP) in a transmission buffer;
at least segmenting or concatenating the RLC SDUs output from the transmission buffer to form at least one RLC protocol data unit (PDU);
adding at least one header to the at least one RLC PDU, each of the at least one header comprising a sequence number (SN) of each of the at least one RLC PDU;
ciphering the at least one RLC PDU as a final data processing step in the UM RLC entity; and
transmitting the ciphered at least one RLC PDU to a lower layer through at least one of a plurality of channels for transmission.
6. The method claim 5 , wherein:
the at least one RLC PDU comprises the at least one header and data; and
the at least one header further includes an optional length indicator.
7. The method of claim 5 , wherein the SN is excluded from the ciphering.
8. The method of claim 5 , further comprising transmitting the ciphered at least one RLC PDU to an RLC entity of the communication system corresponding to a receiving side and at least one of the plurality of channels is DTCH, DCCH, CCCH, SHCCH, or CTCH.