A Practical Perspective
Let's look into the practical perspective of clocks and time in distributed systems.
We'll cover the following...
The clocks used in real systems are what we usually call physical clocks.
Physical clock
A
Most physical clocks are based on cyclic processes. Below are some examples of such devices:
Sundial
A sundial is one of the most basic and easy-to-understand devices. It tells the time of the day by using a gnomon and tracking the shadow created by the sun.
Hourglass
An hourglass is also a basic and easy-to-understand device. It measures time by the regulated flow of sand through a bulb.
Pendulum clock
A pendulum clock is a common clock device that uses an oscillating weight as its timekeeping element.
Quartz clock
A quartz clock is an electronic version of the pendulum clock and is used in software systems. This device makes use of a crystal, called quartz ...