Welcome to the home of the Apereo Central Authentication Service project, more commonly referred to as CAS. CAS is an enterprise multilingual single sign-on solution and identity provider for the web and attempts to be a comprehensive platform for your authentication and authorization needs. CAS is an open and well-documented authentication protocol. The primary implementation of the protocol is an open-source Java server component by the same name hosted here, with support for a plethora of additional authentication protocols and features. Monitor and track application and system behavior, statistics and metrics in real-time. Manage and review audits and logs centrally, and publish data to a variety of downstream systems. Manage and register client applications and services with specific authentication policies. Cross-platform client support (Java, .NET, PHP, Perl, Apache, etc).