95741 Sixth Edition Glossary-5
Glossary
to one another via software and hardware
links, to facilitate information interchange.
NL_Port An N_Port within the Node which
also contains the Loop Port State Machine as
defined in FC-AL-2. The NL_Port attaches to
either an FL_Port or an NL_Port through a
link.
node A device that contains a minimum of
one N_Port and/or NL_Port.

O

offline Neither controlled by, nor
communicating with, a computer. (IBM)
online Pertaining to the operation of a
functional unit when under the direct control
of the computer. (T)
operating system Software that controls
program execution.
operator control panel A functional unit
that contains switches used to control all or
part of a computer and possibly the
indicators giving information about its
functioning. (T)

P

performance One of two major factors,
together with facility, on which the total
productivity of a system depends.
Performance is largely determined by a
combination of throughput, response time,
and availability. (IBM)
point-to-point A topology in which exactly
two ports communicate. In FC, the two ports
are N_Ports.
port A specific communications end point
within a host. A port is identified by a port
number. (IBM) In FC, it is an access point in
a device where a link attaches. Examples of
this port are N_Port, NL_Port, F_Port, and
FL_Port.
private loop An Arbitrated Loop that does
not contain a participating FL_Port but does
contain two or more NL_Ports.
Private NL_Port An NL_Port that does not
attempt a Fabric Login.
protocol A set of semantic and syntactic
rules that determines the behavior of
functional units in achieving communication.
(I).
public loop An Arbitrated Loop that
includes a participating FL_Port and at least
one NL_Port.
Public NL_Port An NL_Port that attempts a
Fabric Login.

R

random access memory (RAM) A storage
device in which data can be written and read.
(IBM).
read/write head The data sensing and
recording unit of a diskette magazine drive or
tape drive. (IBM)
reclaim The process of reformatting a tape
as a data tape.
release A distribution of a new product or
new function and fixes for an existing
product. (IBM)
restore To return a backup copy to the
active storage location for use. (IBM)
rewind To move tape from the take-up hub
to the supply hub. (IBM)

S

SCSI See small computer system interface.
small computer system interface (SCSI)
An input and output bus that provides a
standard interface between the OS/2
multimedia system and peripheral devices.
(IBM)