timed (time
daemon
A demon is a malevolent supernatural being, evil spirit or fiend in religion, occultism, literature, fiction, mythology and folklore.
Demon, daemon or dæmon may also refer to:
Entertainment Fictional entities
* Daemon (G.I. Joe), a character ...
) is an
operating system program that maintains the
system time
In computer science and computer programming, system time represents a computer system's notion of the passage of time. In this sense, ''time'' also includes the passing of calendar date, days on the calendar.
System time is measured by a ''sys ...
in synchronization with time servers using the Time Synchronization Protocol (TSP) developed by Riccardo Gusella and Stefano Zatti. Gusella and Zatti had done earlier related work on their TEMPO algorithm. The Time Synchronization Protocol specification refers to an election algorithm and a synchronization mechanism specified in other technical reports listed as "to appear".
With the release of
macOS High Sierra in 2017, timed in
macOS
macOS, previously OS X and originally Mac OS X, is a Unix, Unix-based operating system developed and marketed by Apple Inc., Apple since 2001. It is the current operating system for Apple's Mac (computer), Mac computers. With ...
has subsumed all time synchronization responsibilities including those of the former
ntpd and timed.
See also
*
Network Time Protocol
The Network Time Protocol (NTP) is a networking protocol for clock synchronization between computer systems over packet-switched, variable-Network latency, latency data networks. In operation since before 1985, NTP is one of the oldest Intern ...
(NTP)
*
Precision Time Protocol
The Precision Time Protocol (PTP) is a protocol for clock synchronization throughout a computer network with relatively high precision and therefore ''potentially'' high accuracy. In a local area network (LAN), accuracy can be sub-microsecon ...
(IEEE 1588 PTP)
References
External links
timed(8) man page*
', System Manager's Manual (SMM:11)
*
', System Manager's Manual (SMM:12)
Network time-related software
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