Method for processing radio protocol in mobile telecommunications system and transmitter of mobile telecommunications
An apparatus and method for performing procedures (protocols) of a PDCP (Packet Data Convergence Protocol) layer and an RLC (radio layer in an E-UMTS (Evolved Universal Mobile Telecommunications System) which has evolved from UMTS, among radio protocols of a mobile communication system. The PDCP layer performs ciphering on data (i.e., PDCP SDU) received from an upper layer, generates an indicator discriminating ciphered data and non-ciphered data (i.e., an ROHC feedback packet directly generated by the PDCP layer), and transmits the same to a lower layer (i.e., MAC layer). A PDCP SN (Sequence Number) is defined as an algorithm for ciphering the data in the PDCP layer to perform ciphering in the PDCP layer.
1. A transmitting device comprising:
a transceiver; and
a processor configured to:
receive a packet data convergence protocol (PDCP) service data unit (SDU) from an upper entity and perform sequence numbering to the received PDCP SDU;
compress a header of the received PDCP SDU;
cipher the header-compressed PDCP SDU;
add a first SN to the ciphered PDCP SDU,
wherein the first SN is added to the ciphered PDCP SDU based on the sequence numbering;
segment the first SN added PDCP SDU;
add a corresponding second SN to each segment of the segmented PDCP SDU; and
process the second SN added segmented PDCP SDU.
2. The transmitting device of claim 1 , further comprising:
a first buffer configured to store the PDCP SDU received from the upper entity.
3. The transmitting device of claim 2 , wherein the first SN-added PDCP SDU is a radio link control (RLC) SDU.
4. The transmitting device of claim 3 , further comprising:
a second buffer configured to receive and store the RLC SDU.
5. The transmitting device of claim 1 , wherein the processor is further configured to generate data independently from the PDCP SDU received from the upper entity.
6. The transmitting device of claim 5 , wherein the generated data is a robust header compression (ROCH) feedback packet.
7. A method for processing data in a transmitting device, the method comprising:
receiving a packet data convergence protocol (PDCP) service data unit (SDU) from an upper entity;
performing sequence numbering to the received PDCP SDU;
compressing a header of the received PDCP SDU;
ciphering the header-compressed PDCP SDU;
adding a first SN to the ciphered PDCP SDU,
wherein the first SN is added to the ciphered PDCP SDU based on the performed sequence numbering;
segmenting the first SN added PDCP SDU;
adding a corresponding second SN to each segment of the segmented PDCP SDU; and
processing the second SN added segmented PDCP SDU.
8. The method of claim 7 , further comprising:
storing, in a first buffer, the PDCP SDU received from the upper entity.
9. The method of claim 8 , wherein the first SN-added PDCP SDU is a radio link control (RLC) SDU.
10. The method of claim 9 , further comprising:
receiving and storing, in a second buffer, the RLC SDU.
11. The method of claim 7 , further comprising:
generating data independently from the PDCP SDU received from the upper entity.
12. The method of claim 11 , wherein the data generated independently from the PDCP SDU received from the upper entity, is a robust header compression (ROCH) feedback packet.