Network Time Servers: NTP Client Software List

NTP Client Software

Our Time Servers are used to synchronize all NTP clients on a network. In addition to NTP, other time protocols supported are SNTP, TIME and DAYTIME.

Two steps are all that is required to establish your synchronized network time source:

1. Connect the time server to your network.

2. Install and configure the client software on each workstation that will interface to the server. Setting up an NTP or SNTP client is relatively simple once you have successfully communicated with your time server over the network.

It is not necessary to purchase expensive client software. In many cases, the client software is already resident in the operating system of the workstation, server or router. In other cases, it is available as freeware, shareware or inexpensive applications. The following list is by no means exhaustive, as there are numerous client software applications available. It is just a sample of what is available and is not a list of recommendations.

For a basic overview of how NTP works, please read our "Introduction to NTP" application note.

Windows 95, 98, NT, 2000, XP, 2003

Windows 2003 - You will need to configure the Windows Time Service by editing some registry entries. Go to Microsoft Support for details.

*Official NTP Reference Distribution for NT/2000/XP: 510 Software Group offers a free, compiled version of the NTP distribution for Windows NT/2000/XP platforms. The download link is in the "Utility Programs for NT" section. If you are serious enough about reliable timekeeping to purchase a Stratum 1 timeserver, we think you should be using "real NTP" client software. It offers robustness and configuration capabilities that can prevent catastrophic synchronization failures. *Highly-recommended.

Windows NT 4.0 Resource Kit - You will need to purchase the Microsoft Windows NT Server Resource Kit to obtain the necessary files for installing the Time Service that communicates with NTP. Refer to Microsoft NT supplement 4: Keeping Time On Your Windows NT Network.

W32Time - Windows 2000 and XP include a built-in time service called Windows Time or W32Time. Go to The Windows Time Service for a detailed description of this service, how it operates on a Windows 2000 network, and how it can be configured to best meet the needs of your enterprise.

Domain Time II - W32Time (see above) was designed to keep the computer clocks within a domain roughly synchronized but was never intended to be an enterprise time solution. It is "good enough" for Kerberos on Windows 2000, but does not attempt to address timing needs beyond that. Domain Time II is more robust and easier to manage than the native W32Time Time Service, and is designed to replace it. For an overview of the problems with a pure Microsoft timekeeping solution click here.

Automachron - is a freeware SNTP client for synchronizing your computer's time with an NTP server. Automachron works under Win95/98, NT4 and Win2000. It supports SNTP as well as TIME (both UDP and TCP).

Tardis 2000 - Tardis is a shareware utility for Windows that makes sure your PC's clock tells the right time. It can find out what the right time is in various ways including accessing Internet-based Atomic Clocks, using networked timeservers, GPS, Radio Clocks, and by listening for time broadcasts over a LAN. Tardis 2000 is rated 5 Cows on Tucows and is used on the International Space Station.

WorldTime - is a feature-packed freeware World Clock. It is a 5 star "Killer Download" on ZDNet and is rated 4 Cows on Tucows. WorldTime uses the Network Time Protocol (NTP) to synchronize your computer system time to a time server.

YATS32 - This application lets you reliably and automatically set your system clock to any of a number of time services available over your corporate intranet. It supports multiple servers and time service protocols such as SNTP and TIME.

Unix/Linux

Several manufacturers include the NTP daemon as part of their OS release. If your OS does not, we suggest you use the original NTP code itself which is freely available from http://www.ntp.org. Documentation is included in the download that provides information on how to install the software on various Unix platforms.

Sun includes the official NTP reference distribution in many versions of their operating systems. For the most recent information, search http://docs.sun.com for "NTP".

Chrony - Chrony is a pair of programs which are used to maintain the accuracy of the system clock on a computer. The two programs are called chronyd (a daemon) and chronyc (a user interface to chronyd for monitoring/configuring). For Linux/Solaris/BSD.

Novell NetWare

Search the Novell Knowledgebase for "NTP" for the most recent documentation.

TIMESYNC.NLM provides a Novell-proprietary time synchronization service which has been available on NetWare since NetWare 4.0 was released in 1993. In 1999 Novell enhanced TIMESYNC.NLM to provide both NTP client and server capability. TIMESYNC.NLM version 5.08 or later provides these facilities. See the July 3, 1999 AppNote, Using Network Time Protocol (NTP) with NetWare 5. For NetWare version 4.2, see Monitoring and Maintaining Time Synchronization.

Cadence Time Services - Cadence is an NLM that becomes a part of the Novell operating system. Not inexpensive.

SNTPCLNT is a Simple Network Time Protocol client shareware for Netware 3.x, 4.x and 5.x.

Apple Macintosh

NTP support is available via the Date and Time Control Panel on Mac OS 8.5 and higher.

NetChronometer is shareware. NetChronometer will synchronize the date and time of your Macintosh with a network time server.

Vremya is a scriptable NTP client for Macintosh. It allows you to set your clock using a NTP server by polling or receiving broadcasts. It requires Open Transport TCP/IP version 1.1 or better.

iSeries and AS/400

Client Server Development makes a product called Atomic Time Manager 400 which synchronizes iSeries and AS/400 hardware and software clocks to an NTP server.

Cisco Routers and Firewalls

Cisco provides online documentation for the IOS system.
IOS 12: You can find the relevant information in the master index of the Configuration Guide.
IOS 10 and 11: Look under "Managing The System" of the Configuration Guide to find NTP configuration information.

Other Firewalls

Symantec Enterprise Firewall - Go to the Products and Services section of the Symantec website and search on NTP. You'll find information on how to configure Network Time Protocol (NTP) on your firewall.

Borderware - Go to the Support section of the Borderware website. Navigate to the "Firewall Server Knowledge Base" and search on "NTP" for directions on how to enable NTP on your firewall.