title: How do I calculate IP-header length?
body: <p>I want to calculate IP-header length with following statement:</p>
  
  <blockquote>
    <p>Header Length is a four-bit field that tells, as the name implies, the
    length of the IP header in 32-bit words</p>
  </blockquote>
  
  <p>Now I'm getting difficulties in calculating IP header length (minimum and maximum), with four-bit field.</p>