Recently I had some issues syncing my switches to the Windows DC PDC Emulator for time. A lot of blogs were saying Windows only supports SNTP and not full blown NTP so we can not! Even Cisco docs say this! These docs are for versions before Windows Server 2008. The only issue I had with using the DC as the NTP server is it was advertised as stratum 16 and the switches didn’t like it. There was a simple fix for this.
So in short, to have your catalyst switches or Routers use your domain controller as an NTP server use the following commands
en conf t ntp server x.x.x.x prefer ntp maxdistance 16