see Mdoc applies the AD as security system. Additionally, Mdoc can use different security layers. In practice this means that in the same directory structure you may have files that only becomes visible if you have the right permissions to view the documents. The individual security layer is represented by different colors.
As a standard Mdoc logs all events on the use of a document in a history field. This can be extended with logging using the encryption and rating system in Mdoc.