IBM 8285 Nways, Installation And User Manual

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usually characterized by a core diameter of 50 to 100
µ
m that will allow a large number of modes to
propagate.
N
network. (1) A configuration of data processing
devices and software connected for information
interchange. (2) An arrangement of nodes and
connecting branches. Connections are made between
data stations. (T)
network administrator. A person who manages the
use and maintenance of a network.
network node interface (NNI). The interface between
two network nodes.
NNI. Network node interface.
node. A generic term applying to an active element in
an ATM network (station or concentrator).
NSAP. Network Service Access Point.
O
optical cable. A fiber, multiple fibers, or a fiber bundle
in a structure built to meet optical, mechanical, and
environmental specifications. (E)
optical fiber. A small-diameter strand made from glass
and/or polymer that consists of a core surrounded by a
lower-index-of-refraction cladding. It guides light from
one end to another by a combination of a graded index
in the core and internal reflectance.
optical fiber cable. Synonym for optical cable.
optical fiber connector. A hardware component that
transfers optical power between two optical fibers or
bundles and is designed to be repeatedly connected and
disconnected.
OSPF. Open Shortest Path First
output device. A device in a data processing system
by which data can be received from the system. (I) (A)
Synonymous with
output unit.
output unit. Synonym for output device.
P
Packet Internet Groper (PING). (1) In Internet
communications, a program used in TCP/IP networks to
test the ability to reach destinations by sending the
destinations an Internet Control Message Protocol
(ICMP) echo request and waiting for a reply. (2) In
communications, a test of reachability.
parameter. (1) A variable that is given a constant
value for a specified application and that may denote the
application. (I) (A) (2) An item in a menu or for which
the user specifies a value or for which the system
provides a value when the menu is interpreted. (3) Data
passed between programs or procedures.
parity. (1) A transmission error-checking scheme in
which an extra bit is added to some unit of data, usually
a byte, in order to make the total number of one bits
even or odd. No-parity means that no parity bit is sent
or expected. Mark and space mean that the parity
position is always set to one or zero, respectively, and
that received parity is not checked. (2) The state of
being either even-numbered or odd-numbered.
parity (even). A condition when the sum of all of the
digits in an array of binary digits is even.
parity (odd). A condition when the sum of all of the
digits in an array of binary digits is odd.
patch cable. A length of cable with data connectors at
both ends that is normally used to interconnect two
sections of building cable at a patch panel or to connect
a product to the building cable. Synonymous with
jumper cable.
patch panel. An organized concentration of cable
terminations, usually mounted in a flat panel, that
facilitates the interconnection of communication cables.
path. (1) In a network, any route between any two
nodes. (T) (2) The route traversed by the information
exchanged between two attaching devices in a network.
PC. Personal computer
permanent virtual connection (PVC). (1) In X.25 and
frame-relay communications, a virtual connection that
has a logical channel permanently assigned to it at each
data terminal equipment (DTE). Call-establishment
protocols are not required. Contrast with
switched virtual
connection (SVC). (2) The logical connection between
two frame-relay terminating equipment stations, either
Glossary
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