Mule ESB allows for authentication of requests via various transport-specific and generic authentication methods. It also supports controlling authorization at the method level on service components. Security is pluggable via the Mule security API, allowing custom implementations. Spring Security 3.0 and Acegi provide authentication and authorization options like JAAS, LDAP, and CAS that can be used to secure Mule services. WS-Security is also supported to provide message-level security via XML signatures and encryption, and SAML is supported for exchanging security information between systems. Other security integrations include encryption strategies, PGP security, and Jaas security.