Typically, you cannot remotely access a file on a file server if the domain controller is not available. A NAS device is usually more stable and has much less administration than a standard server used as a file server. You might want to set up a separate domain controller for the environment that you are thinking about.
Many of the NAS devices that are based on Microsoft Windows Storage Server have file serving along with NAS functionality. This reduces the number you need and is generally a good idea for the Windows environments that they are used in. In this case, you would need a separate Exchange server.
This was first published in August 2005