title: php validation for NTP server
body: <p>I want to add NTP validation in php anyone can help me ?</p>
  
  <p>some of the example of NTP server are :-                 </p>
  
  <p>nist1-ny.ustiming.org<br>
  nist1-nj.ustiming.org<br>
  nist1-pa.ustiming.org<br>
  time-a.nist.gov<br>
  time-b.nist.gov         </p>