Paul Ryan

jojaba

the_elusive

Anil Natha

pkarjala

Eduardo Larequi

Authorizer restricts access to a WordPress site to specific users, typically students enrolled in a university course. It maintains a list of approved users that you can edit to determine who has access. It also replaces the default WordPress login/authorization system with one relying on an external server, such as Google, CAS, LDAP, or an OAuth2 provider. Finally, Authorizer lets you limit invalid login attempts to prevent bots from compromising your users’ accounts.
View or contribute to the plugin source on GitHub: <a href="https://github.com/uhm-coe/authorizer" rel="nofollow ugc">https://github.com/uhm-coe/authorizer</a>
Authorizer requires the following:
<ul>
<li>CAS server (2.x, 3.x, 4.x, 5.x, 6.x, or 7.x) or LDAP server (plugin needs the URL)</li>
<li>PHP extensions: php-ldap, php-curl, php-dom</li>
</ul>
Authorizer provides the following options:
<ul>
<li>Authentication: WordPress accounts; Google accounts; CAS accounts; LDAP accounts; OAuth2 accounts</li>
<li>Login Access: All authenticated users (all local and all external can log in); Only specific users (all local and approved external users can log in)</li>
<li>View Access: Everyone (open access); Only logged in users</li>
<li>Limit Login Attempts: Progressively increase the amount of time required between invalid login attempts.</li>
<li>Shortcode: Use the <code>[authorizer_login_form]</code> shortcode to embed a wp_login_form() outside of wp-login.php.</li>
</ul>

Authorizer

Integrates nicely with Google hosted domain/s. Couldn't be happier with how it works!

Integrates well with Google Logins

I've experimented this plugin on a multisite and everything works pretty well.

Works great even on a multisite setup

Authorizer limits login attempts, restricts access to specific users, and authenticates against external sources (OAuth2, Google, LDAP, or CAS).

Casey Bisson

wpCAS integrates WordPress into an established CAS architecture, allowing centralized management and authentication of user credentials in a heterogeneous environment.
<a href="http://en.wikipedia.org/wiki/Central_Authentication_Service" rel="nofollow ugc">From Wikipedia</a>:
<blockquote>The Central Authentication Service (CAS) is a single sign-on protocol for the web. Its purpose is to permit a user to log into multiple applications simultaneously and automatically. It also allows untrusted web applications to authenticate users without gaining access to a user’s security credentials, such as a password. The name CAS also refers to a software package that implements this protocol.</blockquote>
Users who attempt to login to WordPress are redirected to the central CAS sign-on screen. After the user’s credentials are verified, s/he is then redirected back to the WordPress site. If the CAS username matches the WordPress username, the user is recognized as valid and allowed access.
<a href="http://en.wikipedia.org/wiki/AuthZ" rel="nofollow ugc">Authorization</a> of that user’s capabilities is based on native WordPress settings and functions. CAS only authenticates that the user is who s/he claims to be.
If the CAS user does not have an account in the WordPress site, an administrator defined function can be called to provision the account or do other actions. By default, CAS users without WordPress accounts are simply refused access.

wpCAS

wpCAS integrates WordPress into an established CAS architecture, allowing centralized management and authentication of user credentials in a heterogen …

Authorizer vs wpCAS