Quick Reference Guide

Glossary 285
bus
An information pathway between the components of a
system. Your system contains an expansion bus that
allows the microprocessor to communicate with
controllers for all the various peripheral devices
connected to the system. Your system also contains an
address bus and a data bus for communication between
the microprocessor and RAM.
byte
Eight contiguous bits of information, the basic data
unit used by your system.
C
Abbreviation for Celsius.
CA
Abbreviation for certification authority.
cache
A fast storage area that keeps a copy of data or instructions
for quicker data retrieval. For example, your system's
BIOS may cache ROM code in faster RAM. Or, a
disk-cache utility may reserve RAM in which to store
frequently accessed information from your system's
disk drives; when a program makes a request to a
disk drive for data that is in the cache, the disk-cache
utility can retrieve the data from RAM faster than from
the disk drive.
capability
Refers to the actions that an object can perform, or
actions that can be taken on a managed object.
For example, if a card is hot-pluggable, it is capable
of being replaced while the system power is on.
CDRAM
Abbreviation for cached DRAM, which is a high-speed
DRAM memory chip developed by Mitsubishi that
includes a small SRAM cache.
CD-ROM
Abbreviation for compact disc read-only memory.
CD drives use optical technology to read data from CDs.
CDs are read-only storage devices; you cannot write
new data to a CD with standard CD drives.
CHAP
Acronym for Challenge-Handshake Authentication
Protocol, an authentication scheme used by
PPP servers to validate the identity of the originator
of the connection upon connection or any time later.
chip
A set of microminiaturized, electronic circuits that
are designed for use as processors and memory in
systems. Small chips can hold from a handful to tens
of thousands of transistors. They look like tiny chips of
aluminum, no more than 1/16 inch square by 1/30 inch
thick, which is where the term
chip came from.
Large chips, which can be more than a half inch square,
hold millions of transistors. It is actually only the top
one thousandth of an inch of a chip's surface that holds
the circuits. The rest of it is just a base.
CIM
Acronym for Common Information Model, which is a
model for describing management information from
the DMTF. CIM is implementation independent,
allowing different management applications to collect
the required data from a variety of sources. CIM
includes schemas for systems, networks, applications
and devices, and new schemas will be added. It provides
mapping techniques for interchange of CIM data with
MIB data from SNMP agents.
CIMOM
Acronym for common information model object
manager.
CI/O
Abbreviation for comprehensive input/output.