Security Cas And Open Id

The document discusses security and identity for web applications. It introduces Ruby CAS and OpenID as solutions for centralized authentication. CAS is described as a private, Java-based central authentication service, while OpenID is a public standard for decentralized authentication using vendors. Ruby gems like ruby-openid and rubycas-client allow integrating OpenID and CAS into Rails applications. Other authentication options like LDAP and NTLM are also mentioned briefly.