title: What information is visible to a packet sniffer which intercepted a HTTPS packet?
body: <p>If I make a HTTPS request to</p>
  
  <pre><code>subdomain.example.com/api/login?mytoken=JLK90GFSSFGDS4GFRW0
  </code></pre>
  
  <p>along with uploading a cookie, can a packet sniffer know:</p>
  
  <ul>
  <li>header information</li>
  <li>subdomain I am requesting</li>
  <li>URL parameters</li>
  <li>cookie contents</li>
  <li>whether it is GZIP compressed</li>
  </ul>
  
  <p>In general, what information is encrypted and what is left plain for a HTTPS packet?</p>