DNS service is provided by an ISP as part of an Internet account. You aren't required to use their name servers, but it is recommended.
Many ISPs automatically assign DNS addresses as you dial-in. If you're having difficulty obtaining these settings, they can be determined while connected from within Windows.
For Win9x: from the Start menu choose Run, then enter "winipcfg" which will start the Windows IP config application.
Choose the More Info button to display a section that contains the DNS settings your connection is using. Click the ellipsis button (...) to display the secondary DNS server.
For WinNT or Win2K: enter "ipconfig /all" at the command prompt to list DNS servers.
Now you can use these settings for KPPP.