SSSD is a system daemon that provides access to identity and authentication remote resource through a common framework that can provide caching and offline support to the system.
SSSD provides a set of daemons to manage access to remote directories and authentication mechanisms.
It provides an NSS and PAM interface toward the system and a pluggable backend system to connect to multiple different account sources as well as a D-Bus interface.
It is also the basis to provide client auditing and policy services for centralised identity management systems such as FreeIPA and Active Directory.
In addition, it provides a more robust database to store local users as well as extended user data.
