Moodle plugins directory: User key authentication: Stats | Moodle.org
User key authentication
Authentication ::: auth_userkey
Maintained by 
Catalyst IT, 
Dmitrii Metelkin, 
Brendan Heywood, 
Marcus Boon, 
Adam Riddell
Brendan Heywood, Log in to Moodle using one time user key based login URL. Auth plugin for organising simple SSO (single sign on) between moodle and your external web application.