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Glossary
Nero BackItUp 89
16 Glossary
AES Encryption
The Advanced Encryption Standard uses symmetrical encryption with key lengths of 128,
192, and 256 bits. With it, sensitive data is protected from unauthorized access.
Archive Bit
Archive bits are used to identify files that have been edited. A file is only resaved during the
next backup process if it was edited (and an archive bit is thus reset).
Backup
Copying data from the computer to an alternative storage medium. Backups are created in a
special format with the help of a backup program.
Backup Set
A backup set consists of individual backups that belong together - a complete backup and a
differential backup extension, or a complete backup and one or more incremental backup
extensions.
Bootable CD
Booting refers to loading the operating system when a computer is started. This is normally
done from the hard drive. However, if you do not want to boot or cannot boot your computer
from your hard drive for whatever reason, you can load an operating environment from the
drive with a boot CD.
Classic Encryption
Classic encryption is the predecessor of AES encryption. It uses a symmetrical encryption
algorithm as well. The key length is 56 bits.
CRC
Cyclic Redundance Check refers to an error-detection procedure used during the transmis-
sion or copying of data. A checksum is calculated with a defined amount of data at the be-
ginning, and provided with the data block. After the operation has ended, the checksum is
calculated again and compared to the first value. Deviations indicate the presence of errors.
Differential Backup
Differential backup refers to a type of backup update / backup extension. Only data that has
been modified or added since the first full backup is backed up.
Drive
General term for a storage device with read, and possibly write, capabilities that is located
outside RAM. Drives are e.g. physical drives (hard drives), logical drives (partitions), or opti-
cal drives (CD/DVD drives).