The List of Public Primary (stratum 1) Time Servers

Australia

Location: The University of Melbourne, Melbourne, Australia
Geographic Coordinates: 37:48:09.60S 144:57:29.50E
Synchronization: NTP V4 primary (Trimble Acutime GPS), i386/NetBSD 1.6
Service Area: Australia, New Zealand, Pacific Region
Access Policy: open access, please limit to two peer hosts per site
Contact: David Hornsby (ntp@cs.mu.OZ.AU)
Note: service previously available at 128.250.37.1 moved to 128.250.37.2

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: The University of Melbourne, Melbourne, Australia
Geographic Coordinates: 37:48:09.60S 144:57:29.50E
Synchronization: NTP V4 primary (Magellan OEM GPS), i386/NetBSD 1.6
Service Area: Australia, New Zealand, Pacific Region
Access Policy: open access, please limit to two peer hosts per site
Contact: David Hornsby (ntp@cs.mu.OZ.AU)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Brazil

Location: Laboratory for the Processing of Analog and Digital Signals (PADS), Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.
Geographic Coordinates: Lat: 22°51.7031'S. Lon: 043°13.7045'W. Alt: 25m.
Synchronization: NTP V4 Primary (Garmin Etrex GPS with RA-46 system and 1 PPS external stabilized oscillator), PC/Linux with nanokernel.
Service Area: Brazil, Latin America and Caribbean.
Access Policy: Open access, please limit to two peer hosts (preferentially stratum 2 servers) per domain. Clients (end-users) should use only stratum 2 servers for synchronization.
Contact: Rafael Jorge Csura Szendrodi (szendro@pads.ufrj.br).
Note: IP addresses (IPv4 and IPv6) are subject to change, please use DNS instead!

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Canada

Location: University of Regina, Regina, Saskatchewan, Canada
Geographic Coordinates: 50:25N , 104:35W
Synchronization: NTP V4 Primary (GPS clock), PC/FreeBSD
Service Area: SASK#net, CA*net, Canada
Access Policy: open to stratum2 time servers, others by arrangement.
Contact: Mark Haidl (timekeeper@uregina.ca)
Note: for reliable access please notify with IP of your server

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Organization: Department of Computer Science, University of Calgary
Location: Calgary, Alberta, Canada
Geographic Coordinates: Latitude: 51.0801 Longitude: -114.1281
Synchronization: NTP V4 Primary (GPS clock), UltraSparc/Solaris
Service Area: North America
Access Policy: Open to stratum 2 time servers, others by arrangement. Please notify us.
Contact: Shaun Laing (timemaster@cpsc.ucalgary.ca)
Note: The IP address is subject to change so please use DNS.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Chile

Location: Dpto. Geofísica, Universidad de Chile. Santiago, Chile.
Geographic Coordinates: Lat: 33° 27.19'S. Lon: 70° 39.70'W. Alt: 533m.
Synchronization: NTP V3 primary (GOES OM/DC-468 clock), SunSparc10/SunOS 4.1.3.
Service Area: REUNA and interconnected networks, Chile.
Access Policy: open access, please send a message to notify.
Contact: Gonzalo Pérez (gperez@dgf.uchile.cl)
Note: ntp is an alias and the IP address may change; please use DNS.

Supports following time protocols:
- Daytime Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x_%M_%d_%h:%n:%s_%Y_%z=-4:00

Location: Servicio Hidrografico y Oceanografico de la Armada de Chile
Geographic Coordinates: 33:01,6958S 71:38,1136W (WGS-84)
Synchronization: NTP V4 primary (GPS Clock), i386 Redhat Linux
Service Area: Chile
Access Policy: open access
Contact: Raul Vergara (rvergara@shoa.cl)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Czech Republic

Location: CESNETPrague, The Czech Republic
Geographic Coordinates: 50° 6.11' N, 14° 23.49' E, +252 m
Synchronization: NTP V4 primary (Garmin GPS35), PC / Linux with nanokernel
Service Area: Czech Republic and Slovakia, European academic community
Access Policy: open to servers providing synchronization to ten or more hosts, others by arrangement
Contact: Vladimir Smotlacha (ntp-admin@cesnet.cz)
Note: ntp is an alias and the IP address may change; please use DNS.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Germany

Location: University Erlangen-Nuernberg, D-91058 Erlangen, FRG
Geographic Coordinates: 49.573N 11.028E (from Meinberg GPS 166)
Synchronization: NTP V3 primary (GPS receiver (<1us)), Sun SS10/Unix SunOS 5.6
Service Area: Germany/Europe
Access Policy: open access, pick one of ntp{0,1,2,3}.fau.de
Contact: The Timekeepers (time@informatik.uni-erlangen.de) Note: IP addresses are subject to change; please use DNS

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: University Erlangen-Nuernberg, D-91058 Erlangen, FRG
Geographic Coordinates: 49.573N 11.028E (from Meinberg GPS 166)
Synchronization: NTP V3 primary (DCF77 PZF receiver (<50us)), Sun SS10 SunOS 5.6
Service Area: Germany/Europe
Access Policy: open access, pick one of ntp{0,1,2,3}.fau.de
Contact: The Timekeepers (time@informatik.uni-erlangen.de)
Note: IP addresses are subject to change; please use DNS

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)

Location: University Erlangen-Nuernberg, D-91058 Erlangen, FRG
Geographic Coordinates: 49.573N 11.028E (from Meinberg GPS 166)
Synchronization: NTP V3 primary (GPS receiver (<1us)), Sun SS10/SunOS 5.6
Service Area: Germany/Europe
Access Policy: open access, pick one of ntp{0,1,2,3}.fau.de
Contact: The Timekeepers (time@informatik.uni-erlangen.de)
Note: IP addresses are subject to change; please use DNS

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)

Location: University Erlangen-Nuernberg, D-91058 Erlangen, FRG
Geographic Coordinates: 49.573N 11.028E (from Meinberg GPS 166)
Synchronization: NTP V3 primary (DCF77 PZF receiver (<50us)), Sun SS10/SunOS 5.6
Service Area: Germany/Europe
Access Policy: open access, pick one of ntp{0,1,2,3}.fau.de
Contact: The Timekeepers (time@informatik.uni-erlangen.de)
Note: IP addresses are subject to change; please use DNS

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)

Location: Technische Universitaet Berlin, D-10587 Berlin, FRG
Geographic Coordinates: 52.518N 13.326E
Synchronization: NTP V3 primary (Meinberg GPS 166), Sun 4/65 SunOS4.1.3
Service Area: Germany/Europe
Access Policy: open access
Contact: Gerard Gschwind (gg@cs.tu-berlin.de)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Technische Universitaet Berlin, D-10587 Berlin, FRG
Geographic Coordinates: 52.518N 13.326E
Synchronization: NTP V3 primary (Meinberg GPS 166), SunS10-402 SunOS5.4
Service Area: Germany/Europe
Access Policy: open access
Contact: Gerard Gschwind (gg@cs.tu-berlin.de)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany
Synchronization: NTP V3 primary (Primary standards CS1, CS2), HP9000/744/HP-UX
Service Area: Germany/Europe, others by arrangement
Access Policy: open access, please send a message to notify.
Contact: Dieter Sibold, Ronald Scheffler (ntp-admin@ptb.de)0
Note: ptbtime1.ptb.de is an alias and the IP address may change; please use DNS.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany
Synchronization: NTP V3 primary (PTB's primary standards CS1, CS2), HP9000/744/HP-UX
Service Area: Germany/Europe, others by arrangement
Access Policy: open access, please send a message to notify.
Contact: Dieter Sibold, Ronald Scheffler (ntp-admin@ptb.de)
Note: ptbtime2.ptb.de is an alias and the IP address may change; please use DNS.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%d_%M_%Y_%h:%n:%s_%z

Location: Computer Center University of Stuttgart, D-70550 Stuttgart, Germany
Geographic Coordinates: 48:47N, 9:10E
Synchronization: NTP V3 primary (Meinberg DCF-77 PZF 535/TCXO), IBM RS6000-250, AIX 4.x
Service Area: Germany/Europe
Access Policy: open, preferred for stratum-2 servers providing synchronization to local networks; appreciate email notification
Contact: Walter Wehinger (wehinger@rus.uni-stuttgart.de)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: University of Rennes 1, Britany, France
Synchronization: NTP V3, Datum TymServe 2100L with GPS
Service Area: France/Europe
Access Policy: open access to stratum-2 servers, send a message to notify
Contact: timemaster@cru.fr
Note: use DNS for IP address

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: BNM-SYRTE, Observatoire de Paris, Paris, France
Synchronization: NTP V3, Datum TymServe 2100 with 1PPS
Service Area: France/Europe
Access Policy: open access to stratum-2 servers, but please send a message to notify
Contact: info.bnm-syrte@obspm.fr, More Informations?
Note: Ref: 1PPS from Atomic Clock

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Ireland

Location: Dept. of Information Technology, National University of Ireland, Galway, Ireland
Synchronization: NTPV4 primary (Trimble Acutime GPS), Intel, Linux 6.2
Service Area: Ireland, UK
Access Policy: open access, please send a message to notify
Contact: ntp@it.nuigalway.ie
Note: IP address is subject to change so please use DNS.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Italy

Location: IEN Galileo Ferraris, Torino, Italy
Synchronization: NTP primary (Cesium Beam Frequency Standard), PC/Linux
Service Area: Italy/Europe
Access Policy: open access, pick one of ntp{1,2}.ien.it; please send a message to notify
Contact: ntp.info@ien.it
Note: IP addresses are subject to change; please use DNS

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: IEN Galileo Ferraris, Torino, Italy
Synchronization: NTP primary (Cesium Beam Frequency Standard), PC/Linux
Service Area: Italy/Europe
Access Policy: open access, pick one of ntp{1,2}.ien.it; please send a message to notify
Contact: ntp.info@ien.it
Note: IP addresses are subject to change; please use DNS

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x_%M_%d_%h:%n:%s_%Y_%z=+2:00

Japan

Location: Fukuoka university, Fukuoka, Japan
Geographic Coodinates: 130:21.81E, 33:32.87N
Synchronization: NTP V3.3 primary (GPS clock), Heliostation 400/SunOS 4.1.3
Service Area: Japan/Pacific area
Access Policy: open access
Contact: TSURUOKA Tomoaki (tsuruoka@fukuoka-u.ac.jp), YOSHIMURA Kenji (yosimura@tl.fukuoka-u.ac.jp)
Note: We use a TRAK 8810 GPS STATION CLOCK and a Furuno Electric Co.'s GN-72 GPS receiver respectively.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Mexico

Location: Centro Nacional de Metrologia, Queretaro, Mexico
Geographic Coordinates: 20:32:9.6 N, 100:16:18 W, +1912
Synchronization: Interlock algorithm with direct 1 pps from rimary frequency standard of CENAM, UTC(CENAM)
Service Area: All Mexico and USA
Access policy: Open access
Contact: J. Mauricio Lopez R., jlopez@cenam.mx , 52 4 211 0543

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Netherlands

Location: NLnet, Amsterdam, The Netherlands
Synchronization: NTP primary (GPS), Sun/Unix SunOS 4.1.3
Service Area: The Netherlands/Europe
Access Policy: open access
Contact: beheer@nl.net

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x_%M_%d_%h:%n:%s_%Y_%z

Location: NLnet, Amsterdam, The Netherlands
Synchronization: NTP primary (GPS), Sun/Unix SunOS 4.1.3
Service Area: The Netherlands/Europe
Access Policy: open access
Contact: beheer@nl.net

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x_%M_%d_%h:%n:%s_%Y_%z

Location: NLnet, Amsterdam, The Netherlands
Synchronization: NTP primary (GPS), Sun/Unix SunOS 4.1.3
Service Area: The Netherlands/Europe
Access Policy: open access
Contact: beheer@nl.net

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x_%M_%d_%h:%n:%s_%Y_%z

Norway

Location: The EDB Centre, University of Tromsoe, Norway
Synchronization: NTP V3 primary (GPS clock), HP-UX/Unix
Service Area: NORDUnet
Access Policy: semi-open access, prior arrangment required
Contact: (timekeeper@uit.no)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Poland

Location: Astrogeodynamical Observatory, Space Research Centre, Borowiec, Poland
Synchronization: NTP V3 primary (Caesium clock), PC Pentium, RedHat Linux
Service Area: Poland/Europe
Access Policy: open access
Contact: Robert Diak (kondor@cbk.poznan.pl), Jerzy Nawrocki (nawrocki@cbk.poznan.pl)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x_%M_%d_%h:%n:%s_%Y_%z=+2:00

Singapore

Location: SPRING Singapore
Synchronization: ACTS dial-up using lockclock algorithm; Compaq Alpha UNIX
Service Area: Singapore and Asia
Access Policy: Open to stratum-2 servers and others by arrangement
Contact: Liu YanYing (lyy@spring.gov.sg) 65-67739852

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%j_%y-%m-%d_%h:%n:%s_%x_%x_%e_%v_%z(NIST)_*

Slovenia

Location: J. Stefan Institute, Ljubljana, Slovenia
Geographic Coordinates: 46° 2.517' N, 14° 29.241' E, +363 m (WGS84)
Synchronization: NTP V4 primary (Trimble Palisade GPS), Compaq (DEC) Alpha / Tru64 Unix with MICRO_TIME kernel option
Service Area: Slovenia, European academic community, others by arrangement
Access Policy: restricted to servers providing synchronization to ten or more hosts, please send notification before regular use
Contact: MarkMartinec (timekeeper@ijs.si); More info?
Note: NTP V4 clients preferred for their lower load and better accuracy; IP address subject to change

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Sweden

Location: Netnod Internet Exchange i Sverige AB, Stockholm, SWEDEN (Exchange point Gothenburg, Sweden)
Synchronization: NTP V4 primary (UTC(SP) Swedish National Time Scale via GPS CV),FreeBSD
Service Area: all areas
Access Policy: open access
Contact: Magnus Andersson; See also NTP time server statistics

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Netnod Internet Exchange i Sverige AB, Stockholm, SWEDEN (Exchange point Gothenburg, Sweden)
Synchronization: NTP V4 primary (UTC(SP) Swedish National Time Scale via GPS CV), FreeBSD
Service Area: all areas
Access Policy: open access
Contact: Magnus Andersson; See also NTP time server statistics

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Netnod Internet Exchange i Sverige AB, Stockholm, SWEDEN (Exchange point Malmoe, Sweden)
Synchronization: NTP V4 primary (UTC(SP) Swedish National Time Scale via GPS CV), FreeBSD
Service Area: all areas
Access Policy: open access
Contact: Magnus Andersson; See also NTP time server statistics

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Netnod Internet Exchange i Sverige AB, Stockholm, SWEDEN (Exchange point Malmoe, Sweden)
Synchronization: NTP V4 primary (UTC(SP) Swedish National Time Scale via GPS CV), FreeBSD
Service Area: all areas
Access Policy: open access
Contact: Magnus Andersson; See also NTP time server statistics

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: SP Swedish National Testing and Research Institute, BORAS, SWEDEN
Synchronization: NTP V4 primary (UTC(SP) Swedish National Time Scale), FreeBSD
Service Area: all areas
Access Policy: open access
Contact: Kenneth Jaldehag info@sp.se; See also NTP time server statistics

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: SP Swedish National Testing and Research Institute, BORAS, SWEDEN
Synchronization: NTP V4 primary (UTC(SP) Swedish National Time Scale), FreeBSD
Service Area: all areas
Access Policy: open access
Contact: Kenneth Jaldehag info@sp.se; See also NTP time server statistics

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Netnod Internet Exchange i Sverige AB, Stockholm, SWEDEN (Exchange point Stockholm, Sweden)
Synchronization: NTP V4 primary (UTC(SP) Swedish National Time Scale via GPS CV), FreeBSD
Service Area: all areas
Access Policy: open access
Contact: Magnus Andersson; See also NTP time server statistics

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Netnod Internet Exchange i Sverige AB, Stockholm, SWEDEN (Exchange point Stockholm, Sweden)
Synchronization: NTP V4 primary (UTC(SP) Swedish National Time Scale via GPS CV), FreeBSD
Service Area: all areas
Access Policy: open access
Contact: Magnus Andersson; See also NTP time server statistics

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Stupi AB, Stockholm, SWEDEN
Synchronization: NTP V3 primary (Saphir Cesium Beam Standard/GPS), BSDI Unix
Service Area: SUnet, NORDUnet
Access Policy: open access
Contact: Peter Lothberg (roll@Stupi.SE)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Stupi AB, Stockholm, SWEDEN
Synchronization: NTP V4 primary (HP5071, FreeBSD)
Service Area: Europe
Access Policy: open access
Contact: roll@stupi.se (Peter Lothberg)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Switzerland

Location: Federal Office of Metrology and Accreditation Switzerland (METAS), Bern, Switzerland
Geographic Coordinates: N 46:55:25 E 07:27:51
Synchronization: radiosynchronized receiver locked to HBG transmitter and ACTS dial-up link to METAS T&lab UTC(CH)
Service Area: Switzerland, others by arrangement
Access Policy: open access, please send a message to notify
Contact: Laurent-Guy Bernier (laurent-guy.bernier@metas.ch)
Note: the IP address may change, please use DNS

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)

Location: Integrated Systems Laboratory, Swiss Fed. Inst. of Technology, CH 8092 Zurich, Switzerland
Geographic Coordinates: 47:23N, 8:32E
Synchronization: NTP primary (DCF77 clock), Sun-4/SunOS 4.1.4
Service Area: Switzerland/Europe
Access Policy: open access
Contact: Christoph Wicki (time@iis.ee.ethz.ch)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)

United Kingdom

Location: Falmouth, Cornwall, UK
Synchronization: NTP V3 primary (MSF clock), Sun/Unix
Service Area: JANET
Access Policy: closed access, see notes below.
Contact: jips-nosc@nosc.ja.net
Note: This server is part of the JANET NTP service and is available for JANET stratum-2 clients and for peering with external stratum-1 clocks. Any external stratum-1 peering requests should be emailed to the Contact address.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: University of London Computer Centre, UK
Synchronization: NTP V3 primary (MSF clock), Sun/Unix
Service Area: JANET
Access Policy: closed access, see notes below.
Contact: jips-nosc@nosc.ja.net
Note: This server is part of the JANET NTP service and is available for JANET stratum-2 clients and for peering with external stratum-1 clocks. Any external stratum-1 peering requests should be emailed to the Contact address.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

USA

Alaska

Location: University of Alaska, Fairbanks, AK (147 50 59.7W 64 51 27.3N WGS84)
Synchronization: NTP V3 primary (GPS)
Service Area: Pacific Northwest, others by arrangement
Access Policy: open access for stratum 2 servers
Contact: Rich Schmidt, US Naval Observatory (res@tuttle.usno.navy.mil)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

California

Location: HP Western Research Laboratory, Palo Alto, CA
Synchronization: NTP V4 primary (GPS)
Service Area: NSFNET, BARR region
Access Policy: open access
Contact: ntp-admin@wrl-mail.hpl.hp.com

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Internet Software Consortium, Palo Alto, CA
Geographic Coordinates: 122 9 41 W / 37 26 35 N
Synchronization: NTP primary (GOES clock), BSD UNIX
Service Area: BARRnet, Alternet-west, CIX-west
Access Policy: open access
Contact: Paul Vixie (paul@vix.com)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: ViaNet Communications, Palo Alto, CA, USA
Synchronization: NTP V3 with Trimble Pasisade GPS receiver/FreeBSD
Service Area: All areas
Access Policy: open access
Contact: Joe McGuckin (joe@via.net)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: California Institute of Technology, Pasadena, CA
Synchronization: NTP V3 primary (GPS clock)
Service Area: USA Pacific timezone, others by arrangement
Access Policy: open access for stratum 2 servers

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Datum Inc., Bancomm-Timing Division, San Jose, California
Synchronization: ACTS dial-up using lockclock algorithm; DEC Alpha UNIX
Service Area: Primarily networks in Western US
Access Policy: Open to stratum-2 servers and others by arrangement.
Contact: Judah Levine (jlevine@boulder.nist.gov) 303 492-7785

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%j_%y-%m-%d_%h:%n:%s_%x_%x_%e_%v_%z(NIST)_*

Location: Abovenet, San Jose, California
Synchronization: ACTS dial-up using lockclock algorithm; DEC Alpha UNIX
Service Area: Western US
Access Policy: Open to stratum-2 servers and others by arrangement
Contact: Judah Levine (jlevine@boulder.nist.gov) 303 492-7785

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%j_%y-%m-%d_%h:%n:%s_%x_%x_%e_%v_%z(NIST)_*

Location: NASA Ames Research Center, Moffett Field, CA
Synchronization: NTP V3 primary GPS Clock
Service Area: NSFNET, BARR region, NASA NSN, DOE ESNET, DDN
Access Policy: prior permission required
Contact: clockmaster@ntp.nasa.gov

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: GPSClock.com headquarters, Redondo Beach, CA
Geographic Coordinates: 33:50:26.510N, 118:22:55.245W
Synchronization: NTP V4 primary, GPSClock 300 hard PPS, FreeBSD
Service Area: US Pacific, Los Angeles area
Access Policy: Open to stratum 2 servers for 10 or more hosts, others upon request

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: UCLA, Los Angeles, CA
Synchronization: NTP V3 primary (GPS) HP9000/747i
Service Area: Pacific time zone, others on request
Access Policy: open access to stratum-2 servers and to UCLA clients

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x_%M_%d_%h:%n:%s_%z_%Y

Location: USC Information Sciences Institute, Marina del Rey, CA
Geographic Coordinates: 33:58:49N, 118:26:20W (USGS map NAD27)
Synchronization: NTP V3 primary Datum Tymserve 2100-GPS
Service Area: CalRen2, Los Nettos region
Access Policy: open access
Contact: Information Processing Center (action@isi.edu)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (UDP/IP)

Location: GPSClock.com headquarters, Redondo Beach, CA
Geographic Coordinates: 33:50:26.510N, 118:22:55.245W
Synchronization: NTP V4 primary, GPSClock 200 hard PPS, FreeBSD
Service Area: US Pacific, Los Angeles area
Access Policy: Open to stratum 2 servers for 10 or more hosts, others upon request

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Colorado

Location: Falcon AFB, Colorado
Geographic Coordinates: 104 31 30 W, 38 48 30 N WGS84
Synchronization: NTP V3 primary (USNO Alternate Master Clock H-maser) HP9000/747i
Service Area: USA Pacific and Mountain timezones, others by arrangement.
Access Policy: open access
Contact: Rich Schmidt, US Naval Observatory (res@tuttle.usno.navy.mil)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Falcon AFB, Colorado
Geographic Coordinates: 104 31 30 W, 38 48 30 N WGS84
Synchronization: NTP V3 primary (USNO Alternate Master Clock H-maser) HP9000/747i
Service Area: USA Pacific and Mountain timezones, others by arrangement.
Access Policy: open access
Contact: Rich Schmidt, US Naval Observatory (res@tuttle.usno.navy.mil)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%j_%y-%m-%d_%h:%n:%s_%x_%x_%e_%v_%z(NIST)_*

Location: NIST Boulder Laboratories, Boulder, Colorado
Synchronization: Direct 1 pps from clock ensemble; lockclock algorithm and ACTS dial-up as backup; DEC Alpha/UNIX
Service Area: NSFnet, WESTnet
Access Policy: Open to stratum-2 servers, others by arrangement; please use only one of the servers as primary with the other as a backup.
Contact: Judah Levine (jlevine@boulder.nist.gov) 303 492 7785.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%j_%y-%m-%d_%h:%n:%s_%x_%x_%e_%v_%z(NIST)_*

Location: NIST Boulder Laboratories, Boulder, Colorado
Synchronization: Direct 1 pps from clock ensemble; lockclock algorithm and ACTS dial-up as backup; DEC Alpha/UNIX
Service Area: NSFnet, WESTnet
Access Policy: Open to stratum-2 servers, others by arrangement; please use only one of the servers as primary with the other as a backup.
Contact: Judah Levine (jlevine@boulder.nist.gov) 303 492 7785

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%j_%y-%m-%d_%h:%n:%s_%x_%x_%e_%v_%z(NIST)_*

Location: NIST Boulder Laboratories, Boulder, Colorado
Synchronization: Direct 1 pps from clock ensemble; lockclock algorithm and ACTS dial-up as backup; DEC Alpha/UNIX.
Service Area: NSFnet, WESTnet
Access Policy: Open to servers with at least 10 clients; others by arrangement. please use only one of these servers primary with the other as backup.
Contact: Judah Levine (jlevine@boulder.nist.gov) 303 492 7785.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%j_%y-%m-%d_%h:%n:%s_%x_%x_%e_%v_%z(NIST)_*

Location: National Center for Atmospheric Research, Boulder, Colorado
Geographic Coordinates: 39:58:43.44N 254:43:32.5E +1840m (WGS 84)
Synchronization: ACTS dial-up with NTP backup, DEC Alpha UNIX Service Area: NSFnet, WESTnet
Access Policy: open to stratum-2 servers and others by arrangement
Contact: Judah Levine (jlevine@boulder.nist.gov), (303) 492-7785

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%j_%y-%m-%d_%h:%n:%s_%x_%x_%e_%v_%z(NIST)_*

Location: JILA Laboratory, University of Colorado
Synchronization: ACTS dial-up using lockclock algorithm; DEC Alpha UNIX
Service Area: Western US
Access Policy: Open to All Colorado users, other stratum-2 servers; others by arrangement
Contact: Judah Levine (jlevine@boulder.nist.gov) 303 492-7785

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%j_%y-%m-%d_%h:%n:%s_%x_%x_%e_%v_%z(NIST)_*

District of Columbia

Location: U.S. Naval Observatory, Washington, DC
Geographic Coordinates: 77 03 57.7W 38 55 14.1N WGS84
Synchronization: NTP V3 primary (USNO Master Clocks 1,2, and GPS)
Service Area: USA Eastern timezone, others by arrangement
Access Policy: open access for stratum 2 servers
Contact: Rich Schmidt, US Naval Observatory (res@tuttle.usno.navy.mil)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: U.S. Naval Observatory, Washington, DC
Geographic Coordinates: 38:55:14.01 77:03:58.03 (GPS WGS84)
Synchronization: NTP V3 primary (USNO Master Clock 2, H-maser), HP9000/747i
Service Area: NSFNET
Access Policy: open access
Contact: Rich Schmidt (res@tuttle.usno.navy.mil)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x_%M_%d_%h:%n:%s_%z_%Y

Delaware

Location: University of Delaware, Newark, DE
Geographic Coordinates: 39:40:48.425N, 75:45:02.392W (GPS WGS84)
Synchronization: NTP V4 primary (GPS clock), TrueTime NTS-200-GPS
Service Area: CAIRN, Abilene/vBNS
Access Policy: closed access, except for stratum-2 servers providing synchronization to local networks of ten or more hosts
Contact: Dave Mills <mills@udel.edu>
Note: This server does not implement the NTP control-message protocol

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x,_%M,_%d,_Y,_%h:%n:%s-%z

Location: University of Delaware, Newark, DE
Geographic Coordinates: 39:40:35.8N, 75:44:36.6W (GPS WGS 84)
Synchronization: NTP V3 Primary (GPS clock), TrueTime NTS-100-GPS
Service Area: BBN Planet SER
Access Policy: closed access, except for stratum-2 servers providing synchronization to local networks of ten or more hosts
Contact: Ron Reisor (ron@udel.edu)
Note: This server does not implement the NTP control-message protocol.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: University of Delaware, Newark, DE
Geographic Coordinates: 39:40:48.425N, 75:45:02.392W (GPS WGS84)
Synchronization: NTP V4 primary (GPS clock), Sun IPC/SunOS 4.1.3
Service Area: CAIRN, Abilene/vBNS
Access Policy: closed access, except for stratum-2 servers providing synchronization to local networks of ten or more hosts
Contact: Dave Mills <mills@udel.edu>
Note: service is restricted to NTP Version 4 clients only.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Florida

Location: University of Florida, Gainesville, FL
Synchronization: NTP V3 primary (TrueTime GPS-VME)
Service Area: Eastern time zone US
Access Policy: open access for stratum 2 servers and UFL clients,others by arrangement
Contacts: Rich Schmidt, US Naval Observatory CISE, Univ. Florida <res@tuttle.usno.navy.mil>

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Georgia

Location: Georgia Institute of Technology, Atlanta, GA
Geographic Coordinates: 84 23 40.9W 33 46 30.0N WGS84
Synchronization: NTP V3 primary (GPS clock)
Service Area: USA Eastern timezone, others by arrangement
Access Policy: open access for stratum 2 servers

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x_%M_%d_%h:%n:%s_%z_%Y

Location: The Weather Channel, Atlanta GA
Geographic Coordinates: 33:53:39.94N, 84:27:47.98W
Synchronization: NTP V4 primary (CMDA), Sun/Solaris
Service Area: Primarily Southeastern US
Access policy: Open access for stratum 2 servers
Contact: NTP Administrator
Note: IP addresses are subject to change; please use DNS Important: Access policies subject to change if server is overloaded or abused. No access for dial-up or DHCP systems.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Hawaii

Location: Maui High Performance Computing Center
Geographic Coordinates: 20 44.9286 N, 156 26.4070 W
Synchronization: NTP V3 primary (Brandywine/Motorola Oncore GPS)
Service Area: Hawaii, others on request
Access Policy: open access for stratum 2 servers
Contacts: Rich Schmidt (res@tuttle.usno.navy.mil), MHPCC NTP administrator (ntp@mhpcc.edu)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Illinois

Location: Argonne National Laboratories <http://www.mcs.anl.gov/>, Chicago, IL
Synchronization: NTP V3 primary (Brandywine Syncclock32/Oncore GPS)
Service Area: Central time zone US
Access Policy: open access for stratum 2 servers and ANL clients,others by arrangement
Contacts: Rich Schmidt, US Naval Observatory Bill Nickless, Argonne National Labs <nickless@mcs.anl.gov>

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Massachusetts

Location: Massachusetts Institute of Technology, Cambridge, MA
Synchronization: Motorola Oncore UT+ GPS, xntp3-5.90, FreeBSD 3.2
Service Area: Eastern US
Access Policy: open access
Contact: Robert Morris (rtm@lcs.mit.edu)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Concord, MA
Synchronization: NTP V4 primary, Motorola Oncore VP GPS, Linux
Service Area: Eastern US
Access Policy: open access for stratum 2 servers, please notify
Contact: timekeeper@quidnet.com

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Massachusetts Institute of Technology, Cambridge, MA
Synchronization: NTP V3 primary (GPS) HP9000/747i
Service Area: eastern time zone, others on request
Access Policy: open access to stratum-2 servers and to MIT clients
Contacts: Rich Schmidt (res@tuttle.usno.navy.mil)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x_%M_%d_%h:%n:%s_%z_%Y

Location: Cambridge, MA
Synchronization: Motorola Oncore UT+ GPS, Linux
Service Area: Eastern US
Access Policy: open access
Contact: Kenneth Baker (bakerkj@umich.edu)
Note: IP addresses are subject to change; please use DNS.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: University of Massachusetts at Boston
Geographic Coordinates: 42:18:83N, 71:02:36W.
Synchronization: NTP V3/V4 primary (GPS), TrueTime NTS-200
Service Area: New England
Access Policy: Open access to stratum-2 servers in service area; any SOHO's in Massachusetts.
Contact: Rick Martin (ntp@cs.umb.edu)
Note: IP addresses are subject to change; please use DNS.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x,_%M_%d,_%Y,_%h:%n:%s-%z

Maryland

Location: NIST Central Computer Facility, Gaithersburg, Maryland
Synchronization: ACTS dial-up using lockclock algorithm, DEC Alpha/UNIX
Service Area: NSFnet, SURAnet
Access Policy: Open to stratum-2 servers, others by arrangement; please use one of the servers as primary with the other as a backup.
Contact: Judah Levine (jlevine@boulder`.nist.gov) 303 492 7785

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%j_%y-%m-%d_%h:%n:%s_%x_%x_%e_%v_%z(NIST)_*

Missouri

Location: Washington University, St. Louis, MO
Synchronization: NTP V3 primary (GPS) HP9000/747i
Service Area: USA Central timezone, others by arrangement.
Access Policy: open access
Contact: Rich Schmidt,US Naval Observatory (res@tuttle.usno.navy.mil)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

North Carolina

Location: MCNC, Research Triangle Park, NC
Synchronization: NTP V3 primary (WWVB clock), Netclock/2, Sun 4/65
Service Area: NC-REN region
Access Policy: NC-REN region, other use by prior arrangement
Contact: Tim Seaver (tas@ncren.net, clockmaster@ncren.net)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

New Jersey

Location: Jensen Research Corporation, Oakland NJ
Geographic Coordinates: 41 00.975 N, 74 15.262 W
Synchronization: NTP V4 primary; Præcis Ct CDMA clock; Intel PIII/866 Win2K
Service Area: Eastern US
Access Policy: Closed access, except for stratum-2 servers providing synchronization to local networks of ten or more hosts; others by arrangement only. Please send a message to notify.
Contact: JRC Network Ops (noc@jensenresearch.com) 201 337-4000
Note: IP addresses are subject to change; please use DNS.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

New York

Location: Abovenet, New York City, New York
Synchronization: ACTS dial-up using lockclock algorithm; DEC Alpha UNIX
Service Area: North Eastern US
Access Policy: Open to stratum-2 servers and others by arrangement
Contact: Judah Levine (jlevine@boulder.nist.gov) 303 492-7785

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%j_%y-%m-%d_%h:%n:%s_%x_%x_%e_%v_%z(NIST)_*

Oklahoma

Location: Oklahoma State University, Stillwater, OK
Geographic Coordinates: 97 04 17.0 W, 36 07 19.7 N WGS84
Synchronization: NTP V4 primary (Motorola UT+)
Service Area: Central Time Zone, others by arrangement
Access Policy: open access
Access Policy: open access
Contacts: Rich Schmidt, US Naval Observatory (res@tuttle.usno.navy.mil), Matthew Collier, Oklahoma State University (mwc@okstate.edu)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x_%M_%d_%h:%n:%s_%z_%Y

Pennsylvania

Location: Penn State University, University Park, PA
Synchronization: NTP V3 primary (WWV clock), Sun/Unix
Service Area: NSFNET, PREPNET, JvNCnet
Access Policy: open access
Contact: John Balogh (JohnBalogh@psu.edu) (no longer: jdb@ecl.psu.edu)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Penn State University, University Park, PA
Geographic Coordinates: 40:47:58.1N, 77:51:44.8W (USGS 40077-G7-TF-024)
Synchronization: NTP V3 primary (Traconex/PSTI-1020 WWV clock), Sun/Unix
Service Area: Internet2, vBNS, CERFnet(AT&T IP Services), PSC/NCNE, CASC.
Access Policy: open access
Contact: John Balogh <JDB@psu.edu>
Note: wwv.otc.psu.edu is the CNAME for this service. The IP address WILL change sometime after mid-year 1999; please use DNS.

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Texas

Location: University of Houston, Houston, TX
Geographic Coordinates: 29:43:37N,95:20:22W
Synchronization: NTP V3 primary (GPS) HP9000/747i
Service Area: US Central time zone, others on request
Access Policy: open access to stratum-2 servers and to UH clients
Contacts: Rich Schmidt (res@tuttle.usno.navy.mil), Alan Pfeiffer-Traum (apt@uh.edu)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Utah

Location: XMission Internet, Salt Lake City, Utah
Synchronization: Motorola Oncore UT+ GPS, ntp-4.1.1a, Linux 2.4.18-nano
Service Area: Western US
Access Policy: open access
Contact: ntp@xmission.com

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x_%M_%d_%h:%n:%s_%Y_%z=-7:00

Virginia

Location: Abovenet, Vienna, VA
Synchronization: ACTS dial-up using lockclock algorithm; DEC Alpha UNIX
Service Area: Primarily networks in Eastern US
Access Policy: Open to stratum-2 servers and others by arrangement.
Contact: Judah Levine (jlevine@boulder.nist.gov) 303 492-7785

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%j_%y-%m-%d_%h:%n:%s_%x_%x_%e_%v_%z(NIST)_*

Washington

Location: University of Washington, Seattle, WA
Synchronization: NTP primary (GPS clock), HP9000/747i HPUX
Service Area: Pacific Northwest
Access Policy: open access to Pacific Time Zone stratum 2's and to Univ. of Washington clients; others by arrangement
Contact: Rich Schmidt, USNO, res@tuttle.usno.navy.mil, Bill Mar, Univ. of Washington (bmar@cac.washington.edu)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Location: Microsoft Corporation, Redmond, Washington
Synchronization: ACTS Dial-up and lockclock algorithm, DEC Alpha/UNIX
Service Area: NorthWestNet, NSFnet
Access Policy: open to stratum-2 servers and others by arrangement.
Contact: Judah Levine (jlevine@boulder.nist.gov) (303) 492-7785

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (UDP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%j_%y-%m-%d_%h:%n:%s_%x_%x_%e_%v_%z(NIST)_*

Other

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Time Protocol (UDP/IP)

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (TCP/IP)
- Daytime Protocol (UDP/IP)

DAYTIME timestamp format:
%x_%M_%d_%h:%n:%s_%Y_%z=+2:00

Supports following time protocols:
- Simple Network Time Protocol (UDP/IP)
- Time Protocol (UDP/IP)