Glossary
This glossary defines the special terms,
abbreviations, and acronyms that are used in this
publication.
Numbers

2:1 compression. The relationship between the

quantity of data that can be stored with compression as
compared to the quantity of data that can be stored
without compression. In 2:1 compression, twice as
much data can be stored with compression as can be
stored without compression.
A
A. Ampere.

ac. Alternating current.

access method. A technique for moving data between

main storage and input or output devices.

accessor. This component contains the library robot

and bar code reader. The accessor moves cartridges to
and from the I/O Station, storage slots, and tape
drives.

adapter card. A circuit board that adds function to a

computer.

adj. Adjustment.

AH. The Authentication Header (AH) is intended to

guarantee connectionless integrity and data origin
authentication of IP datagrams. Further, it can
optionally protect against replay attacks by using the
sliding window technique and discarding old packets.

alphanumeric. Pertaining to a character set that

contains letters, numerals, and usually other characters,
such as punctuation marks.

alter. To change.

ambient temperature. The temperature of air or other

media in a designated area, particularly the area
surrounding equipment.
AME. Application Managed Encryption

ampere (A). A unit of measure for electric current that

is equivalent to a flow of one coulomb per second, or
to the current produced by one volt applied across a
resistance of one ohm.

ANSI. American National Standards Institute.

archive. To collect and store files in a designated

place.

ASCII. American National Standard Code for

Information Interchange. A 7 bit coded character set (8
bits including parity check) that consists of control
characters and graphic characters.

assigning a device. The establishing of the

relationship of a device to a running task, process, job,
or program.

assignment. The naming of a specific device to

perform a function.

asynchronous. Pertaining to two or more processes

that do not depend upon the occurrence of specific
events such as common timing signals.

attention (notice). A word for calling attention to the

possibility of danger to a program, device, or system,
or to data. Contrast with caution and danger.

ATTN. Attention.

B

backup. To make additional copies of documents or

software for safekeeping.

bar code. A code representing characters by sets of

parallel bars of varying thickness and separation which
are read optically by transverse scanning.

bar code label. Paper bearing a bar code and having

an adhesive backing. The bar code label must be
affixed to a tape cartridge to enable the library to
identify the cartridge and its volume serial number.

bar code reader. A laser device specialized for

scanning and reading bar codes and converting them
into either the ASCII or EBCDIC digital character code.

Beginning of Partition. See BOP.

bezel. Decorative and safety cover.

bicolored. Having two colors.

bit. Either of the digits 0 or 1 when used in the binary

numbering system.

BOM or bill of materials. A list of specific types and

amounts of direct materials expected to be used to
produce a given job or quantity of output.

BOP. BOP (Beginning of Partition) is a SCSI notion,

which in a single partition format is the same as
H-1