C# SNTP Client

Environment: Visual Studio.NET Beta 1

Though not obvious, time synchronization is sometimes important. The best example is the Kerberos authentication protocol, which requires the resources to be synchronized within minutes or even seconds, but there are other situations as well. The Network Time Protocol (NTP) and its simplified form (SNTP) are widely used to synchronize network resources, due to their simplicity and effectiveness. There are many programs available that synchronize your PC's clock with that of a time server. Dimension 4 is my favorite.

In case you need time synchronization embedded into your software, here is the C# alternative. It's simple, fast and integrates seamlessly with the .NET platform. There is a Java implementation of a NTP client by Michel Van den Bergh, but I don't have the URL anymore. If Michel (or anyone else that knows it) reads this and emails me, then I'll update the article.

There are several time severs on the Internet and the list below contains those operated by NIST. If you need more, you can probably find a few more using any standard Internet search engine.

Name IP Address Location
time-a.nist.gov 129.6.15.28 NIST, Gaithersburg, Maryland
time-b.nist.gov 129.6.15.29 NIST, Gaithersburg, Maryland
time-a.timefreq.bldrdoc.gov 132.163.4.101 NIST, Boulder, Colorado
time-b.timefreq.bldrdoc.gov 132.163.4.102 NIST, Boulder, Colorado
time-c.timefreq.bldrdoc.gov 132.163.4.103 NIST, Boulder, Colorado
utcnist.colorado.edu 128.138.140.44 University of Colorado, Boulder
time.nist.gov 192.43.244.18 NCAR, Boulder, Colorado
time-nw.nist.gov 131.107.1.10 Microsoft, Redmond, Washington
nist1.datum.com 209.0.72.7 Datum, San Jose, California
nist1.dc.certifiedtime.com 216.200.93.8 Abovnet, Virginia
nist1.nyc.certifiedtime.com 208.184.49.9 Abovnet, New York City
nist1.sjc.certifiedtime.com 208.185.146.41 Abovnet, San Jose, California

The server time.nist.gov yields the following results:

The NTPClient class is simply to use. Follow the example below:

NTPClient client;
try 
{
 client = new NTPClient("time.nist.gov");
 client.Connect();
}
catch(Exception e)
{
 Console.WriteLine("ERROR: {0}", e.Message);
 return;
}
Console.Write(client.ToString());

Downloads

Download source - 4 Kb
Download demo project - 7 Kb