Chapter 4 - How to Configure a Fast Ethernet Network
Cable Length
In a Fast Ethernet network, twisted-pair cables have a length limit. No UTP or
STP cable can be more than 100 meters (328 feet) long. A signal cannot be sent
between two end nodes through more than 200 meters of twisted-pair cable.
In a non-uplinked network, all end nodes are thus connected to a hub through
cables that do not exceed 100 meters (328 feet) in length.
For this reason, a non-uplinked network is said to have a maximum diameter of
200 meters (656 feet), as a signal first sent from one end node to the hub where it
is then re-broadcast to another end node.
When configuring a network, users must pay attention to each cable, ensuring
that no cable exceeds the length limit and that this length is well-managed between
end nodes and the hub.
Uplinking
Uplinking a hub with another network expansion device, such as a router,
switch, bridge, or repeater hub allows users to increase the number of ports on a
network. A 100BASE-TX hub can be uplinked with another 10BASE-TX/100BASE-
TX hub through a twisted-pair cable. This is an easy and inexpensive way to
increase the number of interconnected nodes on a network.
Uplinking hubs, however, adds additional network constraints.
The maximum diameter of an uplinked network must not exceed 205 meters
(672.4 feet). Of course, no cable can exceed 100 meters (328 feet) and the total
length between two end nodes must be no longer than 205 meters. Thus, there
can thus be five meters between the uplinked hubs.
How to Configure a Fast Ethernet Network
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