[ntp:questions] Re: Why ntpd is losing out to openntp at OpenBSD (was: Windows - Seven Days Later)

David Woolley david at djwhome.demon.co.uk
Thu Oct 21 06:54:44 UTC 2004

In article <cl6v74$lds$1 at dewey.udel.edu>,
stenn at maccarony.ntp.org (Harlan Stenn) wrote:

> As I understand the RFC for SNTP, Openntpd should advertise itself at
> stratum 15 unless it is being "driven" by an attached refclock, and I
> gather it does not presently support refclocks.

The important word here is "should".  That permits operation without
a local reference clock, but discourages it.  If the intention had beed
to forbid it, the word would have had to be "must".

Also, on a quick look, I think I understand why both Microsoft and OpenBSD's
implementations use 2 as their stratum, regardless of the upstream
stratum.  Microsoft only use this if they  have every been synchronised,
I'm not sure about openntpd.  The following wording suffers from the very
common software documentation problem that it specifies one interface without
specifying how it relates to other interfaces:

      2-15     secondary reference (via NTP or SNTP)

This doesn't say that the number must be greater than the input stratum,
so the typical implementor, who knows how to code, but nothing about the
application, will think that they can use any value in the range.

This also permits acting as both client and server.

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