<ahref="https://en.wikipedia.org/wiki/Universal_2nd_Factor"class="urlextern"title="https://en.wikipedia.org/wiki/Universal_2nd_Factor"rel="nofollow">Universal 2nd Factor</a> (U2F) is an open authentication standard that strengthens and simplifies two-factor authentication using specialized USB or NFC devices.
</p>
<p>
LLNG can propose to users to register their keys. When done, registered user can't login without using its key.
</p>
<divclass="notetip">Note that it's a second factor, not an authentication module. Users are authenticated by both login form and U2F form.
<h2class="sectionedit2"id="prerequisites_and_dependencies">Prerequisites and dependencies</h2>
<divclass="level2">
<p>
This feature uses <ahref="https://metacpan.org/pod/Crypt::U2F::Server::Simple"class="urlextern"title="https://metacpan.org/pod/Crypt::U2F::Server::Simple"rel="nofollow">Crypt::U2F::Server::Simple</a> that is available only via CPAN for now. Before compiling it, you must install Yubico's C library headers (called libu2f-server-dev on Debian).
</p>
</div>
<!-- EDIT2 SECTION "Prerequisites and dependencies" [522-811] -->
In the manager (advanced parameters), you just have to enable it:
</p>
<ul>
<liclass="level1"><divclass="li"> U2F ⇒ Activation: set it to “on”</div>
</li>
<liclass="level1"><divclass="li"> U2F ⇒ Self registration: set it to “on” <em>(to display this application on the menu, create an application that points to <ahref="http://auth.your.domain/u2fregister"class="urlextern"title="http://auth.your.domain/u2fregister"rel="nofollow">http://auth.your.domain/u2fregister</a>)</em></div>
<liclass="level1"><divclass="li"> U2F ⇒ Authentication level: you can overwrite here auth level for U2F registered users. Leave it blank keeps auth level provided by first authentication module <em>(default: 2 for user/password based modules)</em></div>