User guide

Glossary
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840 USE 115 00 Version 1.0
OSI model
Open S
y
stem Interconnection model. A reference standard describin
g
the re
q
uired
performance of devices for data communication. Produced b
y
the International
Standards Or
g
anization.
packet
The unit of data sent across a network.
PING
Packet Internet Groper. A pro
g
ram used to test whether a destination on a network
can be reached.
port
An access point for data entr
y
or exit within a host usin
g
TCP services.
protocol
Describes messa
g
e formats and a set of rules used b
y
two or more devices to
communicate usin
g
those formats.
PLC
Pro
g
rammable Lo
g
ic Controller
repeater
A device that connects two sections of a network and conve
y
s si
g
nals between
them without makin
g
routin
g
decisions or filterin
g
packets.
router
A device that connects two or more sections of a network and allows information to
flow between them. A router examines ever
y
packet it receives and decides
whether to block the packet from the rest of the network or transmit it. The router
will attempt to send the packet throu
g
h the network b
y
the most efficient path.
server
Provides services to clients. This term ma
y
also refer to the computer on which the
service is based.
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