Technical data

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Building a network
Devices in a network
Repeaters
A repeater can be compared to an amplifier, it has no intelligence it only recreates sig-
nals. Signals are attenuated depending on the length of the medium and the frequency
of the signal, which results in a network having a limited range. Using a repeater you
can extend a medium by recreating the signal, thus the signal is identical to its initial
state with regard to strength and appearance. A repeater acts within the same collision
domain (HDPX CSMA/CD) and due to the added latency in each repeater, you can
not install an unlimited number of repeaters in a segment.
Bridge
A bridge separates two or more collision domains and can be used
to connect different topologies. The bridges listen and note which
addresses belong to respective segments, and by doing so the bridge
learns which segment respective devices are connected to.
A bridge is used, for example, when you want to join Ethernet
with Token ring. Bridges usually work selectively, i.e. filters addresses
so that data only reaches the destination address, for example,
devices A and B only communicate on segment 2. In this way the
network is divided up and internal traffic does not load other seg-
ments.
A bridge functions at the MAC layer routing traffic only based on
its physical address. Whereas a router makes decisons based on the
layer 3 addresses
A
1
23
D E
B
C
F
G
H
To k e n
ring
Unit
A
B
C
D
E
F
G
H
Segment
2
2
2
1
1
3
3
3
B A C K