Hitachi STORAGE 9900 - Manual (Page 69)

DRR
Data Recovery and Regeneration.
DSS
Decision Support Systems is a term that refers to computer systems used in the areas of
business intelligence, such as data warehousing, data mining, OLAP, and others.
DTA
Data Adapter.
ECC
Error correction code.
ESA/390 ®
Enterprise Systems Architecture/390 ® . Often abbreviated S/390 ® , ESA/390 is an IBM ®
architecture for mainframe computers and peripherals. Processor systems that follow
this architecture include the IBM ES/9000
® family. In 2000, IBM changed the server
series name to eServer zSeries ™ .
ESCON ®
Enterprise Systems Connection architecture is an IBM mainframe ESA/390 computer
peripheral interface or connection between two mainframes for data exchange. The I/O
interface utilizes ESA/390 logical protocols over a serial interface that configures
attached units to a communication fabric. ESCON is based on networking technology.
ESCON provides direct channel-to-channel connections between mainframe systems
over fiber-optic links at distances up to 43 kilometers or 25 miles. ESCON also
provides a way for communication controllers and other devices to share a single
channel to a mainframe.
ESCON Director
An I/O interface switch that allows the interconnection of multiple ESCON interfaces
in a distributed-star topology.
Ethernet
A Local Area Network (LAN) protocol developed by Xerox ® in cooperation with
Digital Equipment and Intel in 1976. Ethernet supports a star or bus topology and
supports a data transfer rate of 10 megabits per second or 10Mbit/sec. The Ethernet
specification formed the basis of the IEEE 802.3 standard, which specifies the physical
and lower software layers. Ethernet uses the CSMA/CD access method for handling
simultaneous demands and is one of the most widely implemented LAN standards.
Ethernet is also known as 10BaseT. See also Fast Ethernet, Gigabit Ethernet.
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Gl o s s a ry