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Comment by kijeda | Hacker News Reader

I thought NTP was a protocol, not a piece of software. Is the article conflating them, or is there only one single implementation of it that everyone relies upon?

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There's OpenNTPD which is maintained by the OpenBSD/OpenSSH developers. It has been poorly criticized for its focus on security rather than absolute precision, but it's more than adequate for most peoples timekeeping needs.

http://www.openntpd.org/

It has privilege separation, sandboxing and if your OS/distribution uses LibreSSL it implements HTTPS constraints.

http://man.openbsd.org/ntpd.conf.5

http://man.openbsd.org/ntpd.8

http://man.openbsd.org/ntpctl.8

it's more than adequate for most peoples timekeeping needs

Yes it is. I'm on a cable modem and currently using OpenNTPD to talk to 5 NTP servers. My largest offset is currently 3.6 milliseconds. That's fine for general purpose computing. Anyone who needs better should probably buy some NTP or PTP hardware for his LAN.

There is NTP the protocol[1], and there is NTP the implementation[2].

While the implementation is popular, there are alternatives. There is also OpenNTPd, chrony and ntimed for instance.

There are also alternatives to the NTP protocol too, such as PTP and SNTP.

[1]https://www.ietf.org/rfc/rfc5905.txt [2]http://www.ntp.org/

Don't forget the billion-plus machines out there running Windows Time Service (which strangely has had zero security issues I can remember, even when running in server mode).

W32Time has different kinds of issues, in my experience. With it, one's problems tend to be that, by design until very recently, it doesn't provide to-the-second accuracy.

* https://blogs.technet.microsoft.com/askds/2007/10/23/high-ac...

* https://greyware.com/software/domaintime/v5/overview/w32time...

* https://technet.microsoft.com/en-gb/windows-server-docs/iden...

... and TAICLOCK.

* http://cr.yp.to/proto/taiclock.txt

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