Patent ID: 11888979
Assignee: SAMSUNG ELECTRONICS CO., LTD.
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 9:
10. An apparatus for transmitting data in a device to device communication system, the apparatus comprising:
at least one processor configured to:
determine whether a security feature is applied to a packet data convergence protocol (PDCP) service data unit (SDU), and
configure a PDCP protocol data unit (PDU) based on the determination; and

a transmitter configured to transmit the PDCP PDU to a receiving user equipment (UE),
wherein a PDCP header of the PDCP PDU includes an SDU type, a PDCP sequence number (SN), and a first key identification (ID),
wherein, in case that the security feature is applied to the PDCP SDU, the first key ID is set to a value for identifying a first key, the first key being used to generate an encryption key for securing the PDCP SDU and being generated based on a second key identified by a second key ID, and
wherein, in case that the security feature is not applied to the PDCP SDU, the first key ID is set to a zero value.