Huh… is there no backup system in place for that? Why don’t they just use the internet instead given that they are connected to it in the first place. How precise does it need to be and what is it used for, curious why that is a thing.
Accurate time is really important for computers for a lot of reasons.
Cell towers divide time into slots that different phones each get time in. If your time isn’t precise you might speed up or slow down which causes a slot to get a smaller or larger amount of time causing collisions. Handoffs between different towers need accurate timing to know exactly when one tower should release control of a handset.
NTP uses something called stratums. Basically stratum 0 is an atomic clock, stratum 1 is a device that talks to an atomic clock, but internally has its own time keeping. Then all the NTP servers moat people actually use are stratum 2+. Not only that, the Internet adds a ton of jitter because of how unreliable and unpredictable it is.
GPS satellites have atomic clocks on them making them stratum 0. They directly transmit that time. Thus receivers can become stratum 1 and have a very controllable, low jitter time source. Internet NTP isn’t precise enough. This kind of stuff requires microsecond precision.
Huh… is there no backup system in place for that? Why don’t they just use the internet instead given that they are connected to it in the first place. How precise does it need to be and what is it used for, curious why that is a thing.
Accurate time is really important for computers for a lot of reasons.
Cell towers divide time into slots that different phones each get time in. If your time isn’t precise you might speed up or slow down which causes a slot to get a smaller or larger amount of time causing collisions. Handoffs between different towers need accurate timing to know exactly when one tower should release control of a handset.
NTP uses something called stratums. Basically stratum 0 is an atomic clock, stratum 1 is a device that talks to an atomic clock, but internally has its own time keeping. Then all the NTP servers moat people actually use are stratum 2+. Not only that, the Internet adds a ton of jitter because of how unreliable and unpredictable it is.
GPS satellites have atomic clocks on them making them stratum 0. They directly transmit that time. Thus receivers can become stratum 1 and have a very controllable, low jitter time source. Internet NTP isn’t precise enough. This kind of stuff requires microsecond precision.