16.8.2.2 Network timing synchronization status monitoring towards CN

The gNB may receive a request for RAN timing synchronization status (TSS) information from the AMF as specified in TS 23.501 [3]. The RAN TSS information includes one or more of the following attributes: synchronization state, traceable to UTC, traceable to GNSS, frequency stability, clock accuracy, parent time source, as defined in TS 23.501 [3].

The gNB may be pre-configured with a threshold for each RAN TSS attribute it supports. When the gNB detects a primary source event as defined in TS 38.401 [4], a timing synchronisation status report is triggered towards the AMF to provide the current RAN timing synchronisation status information.