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

Claim 5:
6. A method of receiving data in a device to device communication system, the method comprising:
receiving a packet data convergence protocol (PDCP) protocol data unit (PDU); and
processing the PDCP PDU configured based on whether a security feature is applied to a PDCP service data unit (SDU),
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.