User's Guide

Glossary
140 Quantum P4000 and P7000 Libraries User’s Guide
LVD
Low Voltage Differential or LVD. LVD SCSI specifications can
reach distances up to 12 meters. LVD SCSI cabling requires “Twist and
Flat” ribbon cable and an LVD/SE terminator or a “Twist and Flat”
ribbon cable with built-in LVD termination. All IBM and HP LTO tape
drives are LVD devices. Quantum DLT 8000, SDLT 220, and SDLT 320
tape drives can be LVD or HVD devices. Quantum SDLT 600 tape drives
are LVD only.
M
Mixed media This term refers to the use of different tape drive types
within one tape library. mixed media libraries may use DLT and LTO
tape drives simultaneously (LVD), as well as DLT and SDLT tape drives
HVD or LVD).
Mixed media gripper A specialized gripper assembly which will accept
DLT, SDLT, or LTO tape cartridges.
MSBF Mean Swaps Before Failure
MTBF Mean Time Between Failures
MTTR Mean Time To Repair
Multi-unit Refers to linking up to five P4000 and/or P7000 tape libraries
together using Quantum’s Pass Through Mechanism.
N
NEMA National Electrical Manufacturers Association
Network interface Card (NIC) A NIC is a device that handles
communication between a device and other devices on a network.
NVRAM Non-Volatile Random Access Memory is a type of memory that
retains its contents when power is turned off. One type of NVRAM is
SRAM that is made non-volatile by connecting it to a constant power
source such as a battery. Another type of NVRAM uses EEPROM chips to
save its contents when power is turned off. In this case, NVRAM is
composed of a combination of SRAM and EEPROM chips.
P
PCI The PCI bus typically runs at speeds of 33 MHz or 66 MHz and is
usually 32 bits wide. This means that it passes 32 bits of data
simultaneously as if down 32 separate wires. Some of the most recent
computers include “wider” 64-bit PCI buses, and already certain very
high-end video capture cards offer improved performance if connected to
a 64-bit PCI bus.