[ntp:questions] SNTP with 1ms of precision?

Rob nomail at example.com
Thu Jul 8 12:54:01 UTC 2010

Danny Mayer <mayer at ntp.org> wrote:
> There has been no attempt to redefine SNTP. RFC 2030 is 15 years old so
> it's hardly recent. Tools like ntpdate are not SNTP clients by the
> definitions of any RFC you care to name, it just sets the clock. SNTP is
> a simplified protocol to discipline the clock and not just set it.

There are many, many simple devices (printers, routers etc) and even
operating systems out there that provide a time sync option called SNTP
on their config screens.  You set a server address and sometimes an

What nearly all of them do is send a query at the specified (or fixed)
interval, and put the time from the reply packet in the clock, stepping
it to that value.

Maybe it cannot be rightfully called SNTP, but it is what we have.

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