6.2.5 Direct discovery time synchronisation by the Prose Function

24.3343GPPProximity-services (ProSe) User Equipment (UE) to ProSe function protocol aspectsRelease 17Stage 3TS

To ensure time synchronisation as specified in 3GPP TS 33.303 [6], the ProSe Function shall include timing-related information in parameters Current Time and Max Offset as defined in subclause 12.2.2.23 and subclause 12.2.2.24 in the DISCOVERY_RESPONSE message. It shall also include Current Time in MATCH_REPORT_ACK message.

After receiving the Current Time parameter in a DISCOVERY_RESPONSE or MATCH_REPORT_ACK message, the UE shall set the clock used for ProSe to the value of Current Time. After receiving the Max Offset parameter in a DISCOVERY_RESPONSE message, the UE shall store the Max Offset parameter and overwrite any previous value.