2.11BSD/src/usr.sbin/ntp/man/clock.txt

Information on NTP Time Servers and Radio Timecode Receivera

Last updated 1 March 1989

Time Servers

Following is a list of Fuzzball time servers known to be connected to the
Internet and in operation. When more than one address is given, preference
should given to each in order.

Primary Servers

dcn1.arpa (128.4.0.1, 10.2.0.96), U Delaware, Newark, DE
Synchronization: NTP primary (Spectracom WWVB clock)
Service area: ARPANET east (IMP 96), SURANET
Access policy: open access
Contact: Dave Mills (mills@udel.edu)
Note: shares access with dcn5.udel.edu to a single WWVB clock

dcn5.udel.edu (128.4.0.5), U Delaware, Newark, DE
Synchronization: NTP primary (Spectracom WWVB clock)
Service area: ARPANET east (IMP 96), SURANET
Access policy: open access
Contact: Dave Mills (mills@udel.edu)
Note: shares access with dcn1.udel.edu to a single WWVB clock

dcn6.udel.edu (128.4.0.6, 10.2.1.96), Backroom Test Facility, Newark, DE
Synchronization: NTP primary (Precision Standard Time WWV clock)
Service area: ARPANET east (IMP 96), SURANET
Access policy: development test only; please do not access on continuous basis
Contact: Dave Mills (mills@udel.edu)

fordgw.srl.ford.com (128.5.192.1), Ford Research Labs, Dearborn, MI
Synchronization: NTP primary (True Time GOES clock)
Service area: ARPANET east (IMP 111), SURANET
Access policy: closed access; for use only by prior arrangement
Contact: Fred Ball (ball@srlvx0.srl.ford.com)

umd1.umd.edu (128.8.10.1), U Maryland, College Park, MD
Synchronization: NTP primary (Spectracom WWVB clock)
Service area: NSFNET, SURANET
Access policy: open access
Contact: Mike Petry (petry@trantor.umd.edu) or Louie Mamakos
(louie@trantor.umd.edu)

wwvb.isi.edu (128.9.2.129), USC-ISI, Marina del Rey, CA
Synchronization: NTP primary (Spectracom WWVB clock)
Service area: ARPANET west (IMP 27)
Access policy: open access
Contact Steve Casner (casner@isi.edu)

ncarfuzz.ucar.edu (128.116.64.3), NCAR Supercomputer Ctr., Boulder, CO
Synchronization: NTP primary (Spectracom WWVB clock)
Service area: NSFNET, USAN
Access policy: open access
Contact: Don Morris (morris@windom.ucar.edu)

truechimer.cso.uiuc.edu (130.126.174.40), U Illinois, Champaign, IL
Synchronization: NTP primary (Spectracom WWVB clock)
Service area: NSFNET, MIDNET, CICNET, ARPANET central (IMP 94)
Access policy: open access
Contact: Paul Pomes (paul@uxc.cso.uiuc.edu)

fuzz.sdsc.edu (192.12.207.1), SDSC Supercomputer Ctr., San Diego, CA
Synchronization: NTP primary (Spectracom WWVB clock)
Service area: NSFNET
Access policy: open access
Contact: Gerard Newman (gkn@opus.sdsc.edu)

clepsydra.dec.com (128.45.9.54), DEC Western Research Labs, Palo Alto, CA
Synchronization: NTP primary (True Time GOES clock)
Service area: DEC, ARPANET east (IMP 37)
Access policy: closed access; for use only by prior arrangement
Contact: Jeff Mogul (mogul@decwrl.dec.com)

Secondary Servers

fuzzgate.psc.edu (192.5.146.42), PSC Supercomputer Ctr., Pittsburgh, PA
Synchronization: NTP secondary (stratum 2)
Service area: NSFNET
Access policy: open access
Contact: Eugene Hastings (hastings@morgul.psc.edu)

lilben.tn.cornell.edu (192.35.82.50), Cornell U, Ithaca, NY
Synchronization: NTP secondary (stratum 2)
Service area: NSFNET
Access policy: open access
Contact: Dave Mills (mills@udel.edu) on behalf of the Cornell staff

fuzz.csc.org (128.121.54.20), JVNC Supercomputer Ctr., Princeton, NJ
Synchronization: NTP secondary (stratum 2)
Service area: NSFNET
Access policy: open access
Contact: Joanne Boyle (boyle@jvnca.csc.org)

nsfnet-gw.umd.edu (192.41.177.92), U Maryland, College Park, MD
Synchronization: NTP secondary (stratum 2)
Service area: NSFNET, SURANET
Access policy: open access
Contact: Mike Petry (petry@trantor.umd.edu) or Louie Mamakos
(louie@trantor.umd.edu)

libra.rice.edu (128.42.1.64), Rice University
Synchronization: NTP secondary (stratum 2)
Service area: NSFNET, SESQUINET
Access policy: open access
Contact: Farrell Gerbode (gerbode@rice.edu)

Other Servers

macom1.arpa (10.0.0.111, 192.5.8.1), SAIC, Vienna, VA
Synchronization: NTP secondary (stratum 2); line-frequency clock
Service area: ARPANET east (IMP 111), SURANET
Access policy: not recommended, except for testing
Contact: Mike Little (little@macom2.arpa)

swamprat.arpa (192.5.8.6), SAIC, Vienna, VA
Synchronization: local net (stratum 0), line-frequency clock
Service area: ARPANET east (IMP 111), SURANET
Access policy: not recommended, except for testing
Contact: Mike Little (little@macom2.arpa)

patch.arpa (26.6.0.2), USECOM Patch Barracks, Stuttgart, W Germany
Synchronization: NTP secondary (stratum 2), line-frequency clock
Service area: MILNET Europe (IMP 2)
Access policy: not recommended, except for testing
Contact: Buzz Shaw (hshaw@dca-eur.arpa)

dcn3.udel.edu (128.4.0.3), U Delaware, Newark, DE
Synchronization: local net (stratum 0), line-frequency clock
Service area: ARPNET east (IMP 96), SURANET
Access policy: not recommended, except for testing
Contact: Dave Mills (mills@udel.edu)

Radio Timecode Receivers

Following is a list of radio timecode receivers currently on the market. These
devices are attached via a serial asynchronous line, which is used to send
poll messages and receive responses in the following example formats:

Spectracom clock:	<cr><lf>q  ddd hh:mm:ss  tz=zz<cr>	(22 chars)
Truetime clock:		<cr><lf><ctrl-a>ddd:hh:mm:ssq<cr>	(13 chars)
Heath clock:		<cr>hh:mm:ss.f     dd/mm/yr<cr>		(23 chars)
PST clock:		hh:mm:ss.fff  yy/dd/mm/ddd status<cr>	(49 chars)

These formats are exhibited for example only. In some clocks an extensive
repitoire of commands and formats are available.

In the Fuzzball implementation the Spectracom and PST clocks are polled, which
return the time-code string shown, while the other clocks run continuously. In
the Truetime clock the start bit of the last <cr> represents on-time, while in
the other clocks the first <cr> represents on-time. In the time code ddd is
day of year, hh:mm:ss is time of day, f is fractions of seconds, and dd/mm/yr
is conventional (US) date. In the Spectracom clock, q is " " for in-synch or
"?" for off-synch and zz is the time zone (always 00 for UT). In the Truetime
clock, q is a precision estimate in milliseconds and coded as follows: "?"
+-500 msec, "#" +-50 msec, "*" +-5 msec, "." +-1 msec, <sp> less than 1 msec.
In the Heath clock, the hh:mm:ss.f field is displayed as 0?:??:??.? before
synch is first established and hh:mm:ss.? once synch is established and then
lost again.

Model 8170 WWVB Synchronized Clock
Spectracom Corporation
101 Despatch Drive
East Rochester, NY 14445
(716) 381-4827

	This is a LF receiver and decoder for the WWVB station. Several of the
	Fuzzball time servers use this clock. There is no known Unix driver at
	this time. For expected accuracies less than 10 ms, a special
	one-second on-time signal produced by the clock must be used to
	fine-tune the indication.

Model 468-DC Satellite Synchronized Clock
True Time Division, Kinemetrics
3243 Santa Rosa Avenue
Santa Rosa, CA 95401
(707) 528-1230

	This is a UHF receiver and decoder for the GOES satellite. Two
	Fuzzball time servers (ford1.ford.com and bitsy.mit.edu) use this
	clock. Jeff Mogul of DECWRL (mogul@decwrl.dec.com) may provide info
	on a Unix driver.

Model 1020 Integrated Time Source
Precision Standard Time, Inc.
105 Fourier Avenue
Fremont, CA 94539
(415) 656-4447

	This is an HF receiver and decoder for the WWV/WWVH stations. One
	Fuzzball (dcn6.udel.edu) uses this clock. Support for this clock
	was written by Jeff Schiller (schiller@bitsy.mit.edu) of MIT and is
	included in the latest version of the ntpd daemon.

Model GC-1000 Most Accurate Clock
Heath Company
Benton Harbor, MI 49022
(616) 982-3411

	This is an HF receiver and decoder for the WWV/WWVH stations. One
	Fuzzball (dcn6.udel.edu) uses this clock for backup. So far as known,
	there is no Unix driver available. This receiver may no longer be in
	production.

8101 Automated Computer Time Service (ACTS)
Time and Frequency Division, National Bureau of Standards
US Department of Commerce
Gaithersburg, MD 20899

	This is a package of C software for the IBM Personal Computer. It
	can be used to call a special NBS number using either 300-Hz or
	1200-Hz modem and set the computer clock. The latest version has been
	adapted to run on Unix workstations.

Dave Mills sends