Please see the comment to this question by Mark Merrens. The question is completely unclear.
Nevertheless, look at the relevant .NET classes:
System.Net.Dns
,
System.Net.DnsEndPoint
,
System.Net.DnsPermission
; please see:
http://msdn.microsoft.com/en-us/library/btdf6a7e[
^].
What else may you need? Need source code to see how its works? In fact, .NET source code is available, but it is licensed the way we can only use it for debugging purposes, pretty much so. Nevertheless, it should be enough for you if you just want to learn how things work. Please see this article:
http://blogs.msdn.com/b/sburke/archive/2008/01/16/configuring-visual-studio-to-debug-net-framework-source-code.aspx[
^].
There is an alternative way: you can freely download source code of Mono, alternative open-source CLR implementation and learn it. The code in the namespace
System.Net
is supposed to be compliant to the ECMA-335 standard, partition III, so it should be fully compatible with Microsoft .NET. Please see:
http://www.ecma-international.org/publications/standards/Ecma-335.htm[
^],
http://en.wikipedia.org/wiki/Mono_%28software%29[
^],
http://www.mono-project.com/Main_Page[
^].
You can download the source code here:
http://download.mono-project.com/sources/[
^].
By the way, I personally found that working with this stuff was not so hard. For troubleshooting of compatibility-related problems, I even managed to mix .NET and Mono source code in one .NET assembly and pin-pointed and resolved the problems.
—SA