A Practical Guide to Time for Developers: Part 3 — How Computers Share Time

Intro Every action film has that scene just before the military operation begins. “Let’s sync our watches,” the captain says. The idea is simple: if every stage of the plan depends on precise coordination, everyone involved has to act in sync and according to the same timeline. A while ago, we started our journey with a practical goal: synchronizing the time of many computers. To get there, we first had to understand what time actually is and learn the basic glossary needed to speak the language of this problem and its solutions. In the first part ( https://www.dmytrohuz.com/p/a-practical-guide-to-time-for-developers ), we explored the foundations of time itself. In the second ( https://www.dmytrohuz.com/p/a-practical-guide-to-time-for-developers-2ec ), we looked at how time is kept and tracked inside a single computer. Now we are finally ready to move to the next step: how many computers share time with each other. Keeping precise time across many computers is not unusual or exotic. I