Dds-3 Tape Format; Introduction To Dds Recording Format Standards - Seagate STD124000N Product Manual

DDS-3 Tape Format

Introduction to DDS Recording Format Standards

DDS-3 Tape Format
Product Manual
One of the major benefits in DDS technology is in the consistency and strength of
the format standards.
Precise recording format standards provide the basis for well-defined interchange
requirements. DDS format standards define physical cartridge case requirements,
physical and electrical requirements for the unrecorded tape, format requirements
for tape interchange, measurement methods, and test-environment definition and
provide measurable conformance requirements. With this common technical basis
for interchange, vendors can pursue additional technical features or solutions to
differentiate themselves in the market.
The strong standards associated with DDS technology encourage multiple drive and
media vendors worldwide to participate in the technology. Their participation
provides the end-user with a wide range of choices for high-capacity, high-
performance data storage.
While each of the DDS formats has a unique physical and logical format structure,
the purpose of this chapter is to describe the DDS-3 format.
The smallest collection of data supported by the DDS-3 format is a record . A record
is the smallest discrete collection of data that can be supplied by the host to the
Scorpion 24 drive for processing and recording to tape. Conversely, a record also
refers to the smallest collection of data readable by the tape drive from tape, for
reprocessing and transfer back to the host system.
Two types of records are supported: processed records and unprocessed records.
A record may contain processed records, unprocessed records or both. A record
may also contain separator marks .
Note. Separator marks as described in the DDS-3 standard are similar to the terms
set mark and file mark as used in other recording format standards. Typically
separator 1s refer to file marks and separator 2s refer to set marks.
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