Integrity protection for frequent small data transmission

An apparatus of a base station, the apparatus comprising:

• processing circuitry configured to:
• concatenate data of a group of Packet Data Convergence Protocol (PDCP) packets with a security key and a sequence number of a last of the PDCP packets to form concatenated data;
• use a hash function to hash the concatenated data to calculate a hash mark;
• if the sequence number has a 12 or 18 bit length, generating each PDCP packet to contain data of the PDCP packet, the hash mark, and a PDCP header having:
• a first reserved bit that indicates if the hash mark is present in the PDCP packet, and a second reserved bit that indicates if the PDCP packet is used to determine the hash mark;
• if the sequence number has a 7 or 15 bit length, encode, for transmission a user equipment (UE), a PDCP control packet data unit (PDU) comprising:
• the hash mark, a first sequence number (FSN) of the group of PDCP packets, and a PDU type indicating that the PDCP control PDU is an integrity protection packet for the group of PDCP packets;
• and
• encode the PDCP packets for transmission to the UE;
• and
• a memory configured to store the security key.

A non-transitory computer-readable storage medium that stores instructions for execution by one or more processors of a user equipment (UE), the one or more processors to configure the UE to, when the instructions are executed:

• concatenate data of a group of Packet Data Convergence Protocol (PDCP) packets with a security key and a sequence number of a last of the PDCP packets to form concatenated data;
• use a hash function to hash the concatenated data to calculate a hash mark;
• if each PDCP packet has reserved bits, transmit the PDCP packets to a base station, the PDCP packet comprising data of the PDCP packet, the hash mark, and a PDCP header having:
• a first reserved bit that indicates if the hash mark is present in the PDCP packet, and a second reserved bit that indicates if the PDCP packet is used to determine the hash mark;
• if each PDCP packet does not have reserved bits, transmit to the base station:
• a PDCP control packet data unit (PDU) comprising:
• the hash mark, a first sequence number (FSN) of the group of PDCP packets, and a PDU type indicating that the PDCP control PDU is an integrity protection packet for the group of PDCP packets, and
• the PDCP packets.