The Pluggable Authentication Module (PAM) allows applications (in this case, Actian X) to authenticate users with a plug-in mechanism, as an alternative to the default authentication mechanism of a Linux environment. Each plug-in is a shared library that is dynamically loaded into the PAM module.

PAM provides plug-ins for authentication at the operating system level or using third-party solutions, such as LDAP or Kerberos.

PAM allows applications such as Actian X to authenticate users transparently, regardless of the underlying authentication mechanism. Applications do not have to be recompiled or reconfigured if your authentication mechanism changes.