Quick tidbit on Cambium GPS sync source
Synchronization source– Synchronization mode supports two types of timing sources: the timing signal provided by a Cambium Network’s Cluster Management Module (CMM) or by the AP’s own on-board GPS receiver. Both these sources require GPS Synchronization capable AP hardware and …
NTP and NTS time synchronization
Cloudflare has announced its NTS service, which is open to everyone. If you have an NTS client, point it at time.cloudflare.com:1234