Network Time Server

KENIC has set up a NTP Server, ntp.kenic.or.ke, at the Kenya Internet eXchange Point (KIXP) to provide a date and time integrity for computers. Most service providers have implemented time synchronization on their systems utilizing network time servers located in foreign countries. However, the time synchronization services are not extended to their clients due to unreliable connectivity and prohibitive costs associated with international links. Consequently, most of their clients are oblivious of the services' existence.

Implementation of NTP services for the local Internet community utilizes the Global Positioning System (GPS) technology, and is expected to retain 0.5% of the current Internet traffic (NTP traffic) locally therefore enabling the service providers to extend the NTP services to their clients. Organizational expenses saved from operational failures and data losses due to time inconsistencies would be impossible to estimate. Consequently, date and time integrity and accuracy on computerised data information is essential for computer forensics procedures. The increased local content traffic is essential in promoting the development local content and local hosting and ensuring the operational stability of the Internet in Kenya.

There is a need for precision in timing in today's businesses. Here are a few examples:

• Distributed database transaction journalling and logging
• Stock market buy and sell orders
• Secure document timestamps (with cryptographic certification)
• Real Time billing applications such as Voice over IP (VoIP), Fax over IP and electronic banking
• Aviation traffic control and position reporting
• Radio and TV programming launch and monitoring
• Intruder detection, location and reporting
• Multimedia synchronization for real-time teleconferencing
• Interactive simulation event synchronization and ordering
• Network monitoring, measurement and control
• Early detection of failing network infrastructure devices and air conditioning equipment
• Differentiated services traffic engineering
• Distributed network gaming and training

How To

NTP Clients

* The hostname for KENICs' NTP Server is ntp.kenic.or.ke *

Two steps is all that you require to establish your synchronized network time source:

1. Connect the time server to your network. (For ISP's)
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. Your ISP will provide you with the name of your time resource.

There are a wide range of NTP clients available for various platforms. 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.

Windows 95, 98, NT, 2000 and XP

We highly recommend SymmTime - free, convenient multi-zone desktop time utility that automatically synchronizes your system clock to any accessible NTP server.

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.

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 - Tardis is a shareware utility for Windows and is rated 5 Cows on Tucows.

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.

Dimension 4 - time synchronization utility for Windows 95 and Windows NT 4.0. (freeware)

NetTime - a simple time synchronization client for Windows 95/98/NT/2000. Its small, simple unobtrusive and it's free software.

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 the University of Delaware. (This is where NTP was developed.) Downloads are available at 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 NTP public domain software from the University of Delaware 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.

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.

Mac-NTP Direct Download

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.

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.

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

Cisco PIX Firewall - See the section on Cisco IOS Devices

FAQs

Is NTP supported on Multiple platforms?

NTP supports Unix and Windows (XP, NT4 and 2000) systems. Information on the procedures for compiling the distribution and installing it on a typical client or server are available under the specific operating system. The build procedures inspect the system hardware and software environment and automatically select the appropriate options for that environment. While these procedures work with most computers and operating systems marketed today, exceptions requiring manual intervention do exist.

I have installed the NTP Client but still can't synchronise my clocks.

The most common cause for this problem is firewalls on your machine. Firewalls sometimes prevent synchronisation to the time server. It is important therefore to make sure that you consult with your System Admnistrator or support team for advice on how to proceed.

Does NTP support IPv6 and IPv4 addressing?

NTPv4 includes full support for the IPv6 address family, where the operating system supports it, as well as the default IPv4 address family. Either or both families can be used at the same time on the same machine.

What are the Security issues?

NTPv4 includes support for both symmetric key and public key cryptography to prevent accidental or malicious protocol attacks, as well as automatic server discovery using IP multicast means.

Why Use NTP?

Accurate, reliable time is necessary for financial and legal transactions, transportation and distribution systems and many other applications involving widely distributed resources. Without a method for synchronizing systems to a reliable and accurate reference, how do hosts in a large, dispersed networking community know what time it is, or how accurate are their clocks? In a survey involving 94,260 hosts of the Internet system, 20,758 provided local time using three time-transfer protocols. An analysis of the accuracy of the local clocks of these hosts revealed the following:

• Close to half had errors greater than two minutes.
• Ten percent had errors greater than four hours.
• A few had errors over two weeks.

Most local clocks are set by eye to within a minute or two of a wristwatch (as the reference clock) and are rarely checked after that. Many of these local clocks are maintained by some sort of battery-backed clock-calendar device using a room-temperature quartz oscillator that may drift as much as a second per day and can go for weeks between manual corrections.

For many applications, especially distributed Internet applications, much greater accuracy and reliability are required. While the Internet backbone networks and gateways are carefully engineered for good service, operating speeds and service reliability vary considerably. This places severe demands on NTP, which must deliver accurate and reliable time in spite of component failures, service disruptions and possibly poorly engineered implementations.

How does NTP Work?

Primary (stratum 1) servers synchronize to national time standards via radio, satellite and modem.This is what KENIC seeks to provide.

Secondary (stratum 2, ...) servers and clients synchronize to primary servers via hierarchical subnet. The ISPs would provide this server.

Clients and servers operate in master/slave, symmetric and multicast modes with or without cryptographic authentication. Your Client machine is placed here.

Reliability is assured by redundant servers and diverse network paths.

What is NTP?

NTP is a protocol designed to synchronize the clocks of computers over a network. It synchronizes the time of a computer client or server to another server or reference time source, such as a radio or satellite receiver or modem. It provides accuracies typically within a millisecond on LANs and up to a few tens of milliseconds on WANs relative to Coordinated Universal Time (UTC) via a Global Positioning Service (GPS) receiver, for example. Typical NTP configurations utilize multiple redundant servers and diverse network paths in order to achieve high accuracy and reliability.

Large computers and workstations often include NTP software with their operating systems. The client software runs continuously as a background task that periodically gets updates from one or more servers. The client software ignores responses from servers that appear to be sending the wrong time, and averages the results from those that appear to be correct.

Many of the available NTP software clients for personal computers don't do any averaging at all. Instead, they make a single timing request to a signal server (just like a Daytime or Time client) and then use this information to set their computer's clock. The proper name for this type of client is SNTP (Simple Network Time Protocol).