For a bunch of distributed systems nodes need to be roughly matching real time, but also within some tollerance of each other; it's simplest to make everything

For a bunch of distributed systems nodes need to be roughly matching real time, but also within some tollerance of each other; it's simplest to make everything as accurate to real time as possible. I work in broadcast automation. It's a distributed system and the clocks need to be within a certain tolerance of each other. Historically that's done by having a dedicated piece of timekeeping hardware that dictates the station clock, but recently we've been experimenting with using NTP. We have one node (A) where you author time-sensitive events, and another node (B) that polls for pages of those events, loops through them and takes some action when they should occur. Without both nodes agreeing somewhat on the time you'll end up missing events.