Section: 6.36.3 Monitoring and Reporting
Content: The 5G system shall be able to support mechanisms to monitor for timing source failure (e.g., GNSS). The 5G system shall be able to detect when reference timing signals (e.g., from GNSS or other timing source) are no longer viable for network time synchronization. The 5G system shall support a mechanism to determine if there is degradation of the 5G time synchronization. The 5G system shall be able to support mechanisms to indicate to devices (e.g., UEs, applications) that there is an alternate time source available for use (e.g., 5G system internal holdover capability, atomic clock, Sync over Fiber, TBS, GNSS), taking into account the holdover capability of the devices. The 5G system shall be able to detect when a timing source fails or is restored for network time synchronization. The 5G system shall support mechanisms to monitor different time sources and adopt the most appropriate. The 5G system shall support a mechanism to report timing errors such as divergence from UTC and time sync degradation to UEs and 3rd party applications.