Where does this come from, and can I check it?

The Network Time Protocol assigns each time source a stratum number, and each level takes its time from the one above. The figure is taken from IETF, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a technology fact?

Yes. It sits on the Technology shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

What else can I read about it?

The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

Computers set their clocks through a server hierarchy

The Network Time Protocol assigns each time source a stratum number, and each level takes its time from the one above A stratum 0 reference is a physical clock such as an atomic standard or a GPS receiver, and a stratum 1 server sits directly on it. Servers further down the tree synchronise over the network, and each step adds a little error, so deep hierarchies are discouraged. NTP estimates the round trip delay and adjusts for it, keeping ordinary machines within a few milliseconds of each other. It sits in Mondo's technology collection, one of 200 facts that each trace back to the reference below.

Where this comes from

IETF

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Technology trivia

More facts like this

A TCP connection opens with three short messagesBoth ends exchange synchronise and acknowledge packets before any data moves, agreeing on starting sequence numbers Every internet message travels as numbered packetsData is chopped into packets of up to about 1,500 bytes that routes independently and is rebuilt at the far end The local network committee is named after a dateThe IEEE group behind Ethernet and Wi-Fi took its number from the month and year of its first meeting The first ARPANET message was intended to say LOGINIn 1969 the first message sent over ARPANET crashed after transmitting only the letters L and O Unix time counts the seconds elapsed since 1 January 1970Computers use the Unix epoch as a standardized reference point for tracking system time Ethernet was invented at Xerox PARC in 1973Robert Metcalfe designed the wired networking system inspired by the Hawaiian ALOHANET radio system

Tags: time, networking, protocols

Computers set their clocks through a server hierarchy: the short answers

Where does this come from, and can I check it?: The Network Time Protocol assigns each time source a stratum number, and each level takes its time from the one above. The figure is taken from IETF, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a technology fact?: Yes. It sits on the Technology shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.