Product guide

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Appendix C Glossary
MIDI: Musical Instrument Digital Interface. A hardware
specification and protocol used to communicate note and effect
information between synthesizers, computers, keyboards,
controllers and other electronic music devices.
MIRRORING: Also, known as RAID 1 or duplexing (when using
duplicating all data from a primary disk on a secondary disk. The
overhead of requiring 100 percent data duplication can be costly
when using more than two drives. Also see, “Disk Mirroring.”
MMX: Multimedia Extensions. A Pentium processor with 57 new
instructions onboard to accelerate multimedia and
communications applications. Running MMX technology encoded
software on a Pentium processor with MMX technology improves
the speed and smoothness of audio and video playback, image
processing and 3D rendering by more than 60 percent. Current
software (not enhanced with MMX technology) runs 10-20 percent
faster on a Pentium processor with MMX technology.
Modem: Modulator/Demodulator. A device designed to allow
computers to communicate over standard phone lines.
MPEG: Moving Pictures Expert Group. Audio/Video technology
that allows for better than VHS quality video and almost CD
quality audio by utilizing advanced compression techniques.
Non-Volatile Memory: Memory that is maintained even when
power is not on.
On-Board Floppy: A floppy disk drive controller that is
incorporated into the system board.
Open: A circuit that is not complete. Usually accomplished by
removing a jumper from two pins on the system board or a
peripheral card. Also see “Closed” and “Jumper.”
Operating System: The software that provides a link between
application programs and the computer hardware (i.e., disks,
memory).
OSI: Open Systems Interconnection, OSI is the umbrella name
for a series of non-proprietary protocols and specifications, used
with a system of networked computers. The OSI architecture is
split between seven layers, from lowest to highest:
1. Physical layer: this layer determines how signals are
transmitted on the network cabling.
2. Data Link: incorporates the logical link (LLC) and media
access control (MAC) sub layers. The data link layer
transmits data grouped into frames using the Ethernet
or Token ring access methods.
3. Network layer: handles the routing of data in packets
using the networking protocols.
4. Transport layer: ensures error free data transmissions.
5. Session layer: establishes and maintains connections
between nodes according to the appropriate protocol.
6. Presentation layer: handles data encoding and
formatting; provides data compression.
7. Application layer: provides the means for application
processes to use the network services; the interface to
user database, file and E-Mail software often
implemented with API's (application programming
interfaces).
Each OSI layer uses the layer immediately below it and
provides a service to the layer above.
PCI: Peripheral Component Interface. A form of local bus
architecture that provides high-speed interconnection without
directly interfacing with the processor.
Page: Sections of memory consisting of sets of consecutive
bytes. Pages begin on 4-Kb boundaries.