Extensible Firmware Interface Specification
362 12/12/00 Version 1.02
Desktop Management Task Force (DMTF)
The DMTF is a standards organization comprised of companies from all areas of the
computer industry. Its purpose is to create the standards and infrastructure for cost-
effective management of PC systems.
Device Handle
A handle points to a list of one or more protocols that can respond to requests for services
for a given device referred to by the handle.
Device I/O Protocol
A protocol that is used during boot services to access memory and I/O. Also called the
EFI Device I/O Protocol.
Device Path
A variable-length binary data structure that is composed of variable-length generic device
path nodes and is used to define the programmatic path to a logical or physical device.
There are six major types of device paths: Hardware Device Path, ACPI Device Path,
Messaging Device Path, Media Device Path, BIOS Boot Specification Device Path,
and End Of Hardware Device Path.
Device Path Instance
When an EFI Handle represents multiple devices, it is possible for a device path to
contain multiple device paths. An example of this would be a handle that represents
ConsoleOut and consists of both a VGA console and a serial output console. The handle
would send output to both devices and therefore has a device path that consists of two
complete device paths. Each of these paths is a device path instance.
Device Path Node
A variable-length generic data structure that is used to build a device path. Nodes are
distinguished by type, sub-type, length, and path-specific data. See Device Path.
Device Path Protocol
A protocol that is used during boot services to provide the information needed to
construct and manage device paths. Also called the EFI Device Path Protocol.
DHCP
See Dynamic Host Configuration Protocol.
Disk I/O Protocol
A protocol that is used during boot services to abstract Block I/O devices to allow non-
block sized I/O operations. Also called the EFI Disk I/O Protocol.
DMI
See Desktop Management Interface.