title: What is the file with .p8 extension? (APNs Auth Key / JWT)
body: <p>I think it is a little ridiculous but it's hard to find information about what is this file. I've found a lot info how to get this <code>Apple Push Notification Authentication Key</code>, but i also want to know exactly what is it.<br>
  Here is some info i have found:</p>
  
  <p><strong>Benefits:</strong></p>
  
  <ul>
  <li>No need to re-generate the push certificate every year; </li>
  <li>One auth key
  can be used for all your apps; </li>
  <li>Same for sandbox and Production.</li>
  </ul>
  
  <p>From <a href="https://developer.apple.com/library/content/documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/APNSOverview.html" rel="noreferrer">Apple Docs</a>:</p>
  
  <blockquote>
    <p>Token-based provider connection trust: A provider using the
    HTTP/2-based API can use JSON web tokens (JWT) to provide validation
    credentials for connection with APNs. In this scheme, you provision a
    public key to be retained by Apple, and a private key which you retain
    and protect. Your providers then use your private key to generate and
    sign JWT provider authentication tokens. Each of your push
    notification requests must include a provider authentication token.</p>
    
    <p>You can use a single, token-based connection between a provider and
    APNs can to send push notification requests to all the apps whose
    bundle IDs are listed in your online developer account.</p>
    
    <p>Every push notification request results in an HTTP/2 response from
    APNs, returning details on success or failure to your provider.
    Further check <strong>Token-Based Provider-to-APNs Trust</strong> section.</p>
  </blockquote>
  
  <p><strong>Questions:</strong></p>
  
  <ul>
  <li>What is actually the .p8 file?</li>
  <li>What programm can open it? (Keychain didn't work for me)</li>
  <li>Is there a way to convert it to <code>.pem</code> or <code>.p12</code>?</li>
  <li>A little flow-out question in order to not create a new topic: Does the server side operate with .p8 the same way as .p12 or it should be additional tools added?</li>
  </ul>