Device Classes Managing devices requires the operating system to comprehend what device connections are allowed. Functional classes consist of devices that perform the same function. Printers, for example, comprise a functional class. Functional classes are grouped into subclasses according to certain device similarities. For example, printers have a serial or parallel interface.
Serial printers are one subclass and parallel printers are another.
Device types are classified according to their model and manufacturer. Device classes define valid parent-child connections for the operating system. The hierarchy defines the possible subclasses that can be connected for each of the possible child connection locations. Device Configuration Database Device information is contained in a predefined database or a customized database that makes up the device configuration database. The predefined database contains configuration data for all possible devices supported by the system.