Section: 6.6.3 UP confidentiality mechanisms
Content: The PDCP protocol, as specified in TS 38.323[ NR; Packet Data Convergence Protocol (PDCP) specification ]  [23] between the UE and the NG-RAN, shall be responsible for user plane data confidentiality protection. The use and mode of operation of the 128-bit NEA algorithms are specified in Annex D. The input parameters to the 128-bit NEA algorithms as described in Annex D are the message packet, an 128-bit cipher key KUPenc as KEY, a 5-bit bearer identity BEARER which value is assigned as specified by TS 38.323[ NR; Packet Data Convergence Protocol (PDCP) specification ]  [23], the 1-bit direction of transmission DIRECTION, the length of the keystream required LENGTH and a bearer specific, and direction dependent 32-bit input COUNT which corresponds to the 32-bit PDCP COUNT.