wpCAS

wpCAS integrates WordPress into an established CAS architecture, allowing centralized management and authentication of user credentials in a heterogeneous environment.

From Wikipedia :

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.

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.

Authorization 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.

1. 01Download phpCAS and place it on your webserver so that it can be included by the wpCAS plugin.
2. 02Place the plugin folder in your wp-content/plugins/ directory and activate it.
3. 03Set any options you want in Settings -> wpCAS or in the wpcas-conf.php file.
4. 04The plugin starts intercepting authentication attempts as soon as you activate it. Use another browser or another computer to test the configuration.

wpcas-conf.php

wpCAS can be configured either via the settings page in the WordPress dashboard, or via a configuration file. See wpcas-conf-sample.php for an example. If a config file is used, it overrides any settings that might have been made via the settings page and that page is hidden.