MCSA/MCSE Self-Paced Training Kit (Exam 70-270): Installing ...

Glossary G-11
direct memory access (DMA) channel A channel for direct memory access that
does not involve the microprocessor, providing data transfer directly between
memory and a disk drive.
directory Stores information about network resources, as well as all the services that
make the information available and useful. The resources stored in the directory—
such as user data, printers, servers, databases, groups, computers, and security
policies—are known as objects. The directory is part of Active Directory.
directory service A network service that identifies all resources on a network and
makes them accessible to users and applications.
Disk Cleanup A utility that calculates the amount of space that you can gain by
deleting certain types of files, such as temporary files and downloaded program
files.
Disk Defragmenter The program used in Windows XP to defragment a disk.
disk duplexing See disk mirroring, fault tolerance.
disk duplication An automated installation in which you use the System Preparation
tool to create an image from a computer running Windows XP Professional, and
then clone that image on other computers. Using disk duplication usually requires
third-party software.
diskless computers Computers that have neither a floppy disk nor a hard disk.
Diskless computers depend on special ROM to provide users with an interface
through which they can log on to the network.
Disk Management The name of the Windows XP utility used to manage fixed and
removable disks, as well as to create and manage volumes and partitions.
disk mirroring A technique, also known as disk duplicating, in which all or part of
a hard disk is duplicated onto one or more hard disks, each of which ideally is
attached to its own controller. With disk mirroring, any change made to the original
disk is simultaneously made to the other disk or disks. Disk mirroring is used
in situations in which a backup copy of current data must be maintained at all
times. See also disk striping, fault tolerance.
Diskpart A command used to execute disk-management tasks from a command
prompt and to create scripts for automating tasks that you need to perform frequently
or on multiple computers.
disk quota A feature that allows you to allocate disk space to users based on the files
and folders that they own.
disk striping Divides data into 64-Kb blocks and spreads it equally at a fixed rate
and in a fixed order among all disks in an array. However, disk striping does not
provide any fault tolerance because there is no data redundancy. If any partition
in the set fails, all data is lost. See also disk mirroring, fault tolerance.