If your website is in a Windows domain and running Umbraco 4.8 or higher, this package will enable your users to log in to the Umbraco back office with their Windows (Active Directory) accounts, in stead of Umbraco accounts.
Access will be limited to accounts which are members of certain Active Directory groups. The administrator is able to enter the names of these (pre-existing) groups into a custom tree in the Umbraco users section, which is created by the package. From this custom tree, the default Umbraco type (administrator, editor, writer etc.) can be set per Active Directory group, as well as the default access to the various sections of the back office (Content, Media etc.)
These access rights are only assigned upon first login of the user account. Afterwards, access rights have to be changed on a per user basis from the Umbraco back office in the usual way. I.e. there is no group-based management of user rights after the first login.
After installing the package, manual changes to configuration files are necessary, to change the default values to values specificfor your domain. These changes are described in detail in the documentation. Configuration of this package requires access to Umbraco configuration files, as well as some information on LDAP paths and AD accounts specific to your domain.