title: Using OAuth2 Implicit Flow(IdentityServer4), do users have to re-input password every expiration of access token?
body: <p>I need to implement Authorization/Authentication for an Angular2 Client Side WebApp to talk to a Resource Server(WebApi).</p>
  
  <p>I am investigating IdentiyServer4 and choosing a Grant Type / Flow. <a href="http://docs.identityserver.io/en/release/topics/grant_types.html" rel="nofollow noreferrer">HERE</a></p>
  
  <ol>
  <li>Resource Owner Password Credentials Grant(What we use now.) "This is so called “non-interactive” authentication and is generally not recommended".</li>
  <li>Authorization Code &amp; Hybrid &lt;- Solution to Implicit Flow not allowing Refresh Tokens.(Seems fairly complex to me.  But is this the way to go?)</li>
  <li>Implicit Flow - Recommended for SPA's everywhere I look.  But does not support Refresh Tokens..  </li>
  </ol>
  
  <p>With Implicit Flow, how do I not require the user of the SPA to have to type in a password every say 3600 sec?  A recommended access_token lifetime.  I presume there is something I do not understand about getting the new authorization URL.</p>
  
  <p>Resources I have looked at.</p>
  
  <ul>
  <li><a href="http://docs.identityserver.io/en/release/topics/grant_types.html" rel="nofollow noreferrer">IdentityServer4 Grant Types</a></li>
  <li><a href="https://developer.yahoo.com/oauth2/guide/flows_implicitgrant/" rel="nofollow noreferrer">Implicit Grant Flow for Client-Side Apps</a></li>
  <li><a href="https://alexbilbie.com/guide-to-oauth-2-grants/" rel="nofollow noreferrer">A Guide To OAuth 2.0 Grants</a></li>
  <li><a href="https://stackoverflow.com/questions/23517987/oauth2-implicit-flow-with-single-page-app-refreshing-access-tokens">SO - Oauth2 Implicit Flow with single-page-app refreshing access tokens</a></li>
  </ul>
  
  <p>Thanks for the answer Scott.  I have some reading to do.</p>
  
  <ul>
  <li><a href="https://www.scottbrady91.com/Identity-Server/Getting-Started-with-IdentityServer-4" rel="nofollow noreferrer">Getting Started with IdentityServer4</a> </li>
  </ul>