348
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Glossary
WAGO-I/O-SYSTEM
750
BACnet/IP Controller
R
Repeater
Repeaters operate (like hubs, but with only one, instead of several outputs)
on Layer 1 of the
ISO/OSI
model.
Repeaters are physical amplifiers without their own processing function.
They refresh data without detecting damaged data and forward all signals.
Repeaters are used for implementing greater transmission distances, or when
the maximum number of nodes of (normally) 64 devices for each
twisted-
pair
segment is exceeded. The repeater is then always counted as a node in a
segment
when the maximum number of nodes is reached.
The media can also be changed when
routers
are used that are configured as
repeaters.
Request
A service request from a
client
, which requests the provision of a
service
from a
server
.
Response
Response from a server in reply to a
request
from a client.
RFC Specifications
Specifications, suggestions, ideas and guidelines regarding the Internet are
published in the form of RFCs (Request For Comments).
RJ45 Connector
The RJ45 plug is also referred to as a Western connector. This connector
creates the connection of two network controllers via a twisted-pair cable.
Router
Routers are used to connect neighboring
subnets
, with the router operating
with addresses and protocols of the third
ISO/OSI
layer. As this layer is
hardware independent, the routers allow transition to another transmission
medium.
To transmit a message the router evaluates the logical address (source and
destination address) and finds the best path if there are several possibilities.
Routers can be operated in the
Repeater
or
Bridge
modes.
Routing
Method of selecting the best path for sending data to a distant network.
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