>>>>> "Per" == Per Hedeland writes:

Per> Again AFAIK, Windows currently uses (S)NTP (though of course
Per> they don't *quite* follow the standard), so it should
Per> certainly be possible to make them work together, just that
Per> the quality of the result may not be ideal.

Windows Server 2003 and Windows XP both support NTP, though there are
some questions as to the quality of the implementation. Computers
running Windows 2000 only support SNTP. I configured all of my
FreeBSD servers to synchronize their clocks via NTP with my domain
controller (Windows Small Business Server 2003), which in turn is
configured to synchronize with 0-2.us.pool.ntp.org (see "How to
configure an authoritative time server in Windows Server 2003" at
http://support.microsoft.com/kb/816042). My network is so small that
it isn't an ideal implementation, but it works for me:

xenophon@cinep010bsdmx:~>cat /etc/ntp.conf
server irtnog.org
ntpq> peers
remote refid st t when poll reach delay offset jitter
*svr1.irtnog.org 3 u 233 1024 377 33.364 26.773 0.887
ntpq> assoc
ind assID status conf reach auth condition last_event cnt
1 48212 b614 yes yes none sys.peer reachable 1
ntpq> pstatus 48212
status=b614 reach, conf, sel_sys.peer, 1 event, event_reach,
srcadr=svr1.irtnog.org, srcport=123, dstadr=, dstport=123,
leap=00, stratum=3, precision=-6, rootdelay=90.591,
rootdispersion=89.935, refid=, reach=377, unreach=0,
hmode=3, pmode=4, hpoll=10, ppoll=10, flash=00 ok, keyid=0, ttl=0,
offset=26.773, delay=33.364, dispersion=30.406, jitter=0.887,
reftime=ca0e9052.d4e73604 Mon, Jun 4 2007 9:21:22.831,
org=ca0e926f.2cf79852 Mon, Jun 4 2007 9:30:23.175,
rec=ca0e926f.2a62473b Mon, Jun 4 2007 9:30:23.165,
xmt=ca0e926f.21d7bb9b Mon, Jun 4 2007 9:30:23.132,
filtdelay= 33.36 1.71 1.74 1.59 1.65 1.61 1.54 1.55,
filtoffset= 26.77 25.89 18.54 23.49 12.77 30.36 41.04 31.94,
filtdisp= 15.63 31.02 46.38 61.77 77.11 92.49 107.83 123.19

(One of these days I'm going to get Zenoss running so I can chart
meaningless data on my home network like bandwidth utilization and
clock accuracy.)

I suspect that Microsoft wasn't aiming for sub-millisecond accuracy in
their NTP implementation, especially since the default settings for
Active Directory's Kerberos 5 implementation allow up to a five-minute
clock skew between an KDC and the Kerberos client. I suppose that if
I really needed it, I could replace W32time with ntpd or openntp
easily enough. A native (pure win32, not cygwin) port of ntpd used to
be available from somewhere.

(I probably need to add some ACLs or something to my stock NTP
configuration, so that attackers can't mess with the clocks on my UNIX

Best wishes,

"Rogues are very keen in their profession, and know already much more
than we can teach them respecting their several kinds of roguery."
- A. C. Hobbs in _Locks and Safes_ (1853)