User's Guide

Chapter 3 Installing External Tape Drives
Parity Checking
DDS-4/DAT 72 User’s Guide 39
Figure 15 Back Panel of the
External Tape Drive
Parity Checking 3
By default, parity checking is enabled on the external tape drive. If you
disable parity checking, the drive still generates a parity bit.
Data Compression 3
By default, data compression is enabled. With this setting, the external
tape drive compresses all data written to tape and decompresses all
compressed data read from tape. The degree of compression varies due to
the type of data being processed.
• Data with a high degree of redundancy, such as structured database
files or graphics files, are compressed most efficiently, often at a ratio
of 2:1 or more.
• Data with little redundancy, such as executable programs, are
compressed the least.
68-pin wide SCSI
connectors
SCSI ID selector