Ars Technica reported last week that he had peacefully passed away on January 17th. Mills was responsible for the profoundly important creation of Network Time Protocol (NTP), the protocol that underpins the synchronization of networked computers across the world. Ars also pointed to a 2022 New Yorker profile that tells how Mills became the authority on internet time-keeping. Here is a time-stamped link to his explanation of NTP’s history in a 2005 presentation.