A clock tick is a periodic time source to keep track of time delays and time outs.

Multiple time sources may be combined to derive a more accurate time synchronization sources.

A common time source to synchronize all member systems' clocks.

If a trusted time source cannot be obtained or is not running within specified tolerances, transient private keys are not issued.

Big time source right in the middle, very useful.

This can be a pitfall for administrators setting up an in-house time server with no true time source.

Sequence of events recorders usually have an external time source such as a GPS or radio clock.

Stratum 1 time sources are what most people mean when they talk about a time server.

Right now, it's a big time source of copyright violations that shockingly isn't being sued out of existence.

The Berkeley algorithm is a method of clock synchronisation in distributed computing which assumes no machine has an accurate time source.