Device discovery is the term used to describe the process of discovering the disks that are attached to a host. This feature is an important feature because DMP needs to support a growing number of disk arrays from a number of vendors. With the ability to discover the devices attached to a host, the Device Discovery service enables you to add support dynamically for new disk arrays. This operation, which uses a facility called the device discovery layer (DDL), is achieved by using Windows PnP (plug and play ) notifications without the need for any command or user intervention.