Exactly the same question as this one, but for Fedora 26 in 2017: https://askubuntu.com/questions/217463/what-is-the-package-and-background-process-for-network-time#232486
In Fedora 26 Workstation (Gnome), if you open 'All Settings' and then choose 'Date & Time' from the 'System' menu, there is an option for 'Automatic Date & Time' which requires Internet access.
What background process controls this? It doesn't seem to be ntpd. Is there a particular package associated with this feature?
(By the way, if there is a method to figure out the answer to a question like this, that would be nice to know).