Section: 6.6.4.2 UP integrity mechanisms between the UE and the gNB
Content: The use and mode of operation of the 128-bit NIA algorithms are specified in Annex D. The input parameters to the 128-bit NIA algorithms as described in Annex D are, the message packet, a 128-bit integrity key KUPint as KEY, a 5-bit bearer identity BEARER value of which is assigned as specified by TS 38.323[ NR; Packet Data Convergence Protocol (PDCP) specification ]  [23], the 1-bit direction of transmission DIRECTION, and a bearer specific, and direction dependent 32-bit input COUNT which corresponds to the 32-bit PDCP COUNT. If the gNB or the UE receives a PDCP PDU which fails integrity check with faulty or missing MAC-I after the start of integrity protection, the PDU shall be discarded.