phpbb Multiple domain Single Sign on with wordpress plugin
What these code modifications do, is to create a single sign on across different, multiple domains for both phpbb and other sites/codes/apps to use.
These modifications use phpbb user tables, sessions, everything.
What it does is to set cookies for each domain through using iframes, which load some connect.php file that is placed on the other remote domains which needs authentication from phpbb. This is how numerous sites like facebook do it. Currently there is no other way of legally setting cookies for different domains than the one that is active. You have to have a page that loads up all the cookie setting codes from remote domains.
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QuickSSO is a powerful and easy-to-configure cross-domain Single-Sign-On solution. The server is implemented by J2EE, but it does not restrict your develop language. You can add your application to SSO not only B/S application but also C/S one.