title: login form how to give access only to one device
body: <p>For learning reason, trying to give login access only for one device
  so I added new row inside user table in database called ip which stored registered user ip then for example I did something like that</p>
  
  <pre><code>if($user-&gt;ip == $myip){ echo 'success'; }
  </code></pre>
  
  <p>the problem here that ip changing so the form can't let me access or logged in,
  So my question is there anyway to logged in from only by using one device without using ip ?</p>