IBM SAN32M1, Installation And Service Manual

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SAN32M1 Fabric Switch Installation and Service Manual 564
open systems mode
The mode that is used for IBM or open fabrics. See also operating
mode ; S/390 mode .
operating mode In directors or switches, in managed products, a selection between
s/390 and open systems mode. See also
open systems mode ; S/390
mode .
operating system
OS. Software that controls execution of applications and provides ser-
vices such as resource allocation, scheduling, I/O control, and data
management. Most operating systems are predominantly software,
but partial hardware implementations are possible (D, T).
Operating System/390
OS/390™. An integrated, open-enterprise server operating system
developed by IBM that incorporates a leading-edge and open com-
munications server, distributed data and file services, parallel Sys-
plex™ support, object-oriented programming, distributed computing
environment, and open application interfaces (D).
optical cable Single fiber, multiple fibers, or a fiber bundle in a structure built to
meet optical, mechanical, and environmental specifications (D, E). See
also
jumper cable ; trunk cable . Synonymous with fiber-optic cable .
optical drive backup
A data backup system that uses rewriteable optical cartridges (ROCs)
as the storage medium.
optical fiber connector Synonymous with connector .
ordered set In Fibre Channel protocol, four 10-bit characters (a combination of
data and special characters) providing low-level link functions, such
as frame demarcation and signaling between two ends of a link. It
provides for initialization of the link after power-on and for some
basic recovery functions.
original equipment
manufacturer
OEM. A company that has a special relationship with computer pro-
ducers. OEMs buy components and customize them for a particular
application. They sell the customized computer under their own
name. OEMs may not actually be the original manufacturers. They
are usually the customizers and marketers.
OS
See operating system .
OS/390™ See Operating System/390 .
OSI
See Open Systems Architecture .