There
are three cable types commonly used for Ethernet cabling: coaxial,
twisted pair, and fiber-optic cabling. In today's LANs, the twisted pair
cabling is the most popular type of cabling, but the fiber-optic
cabling usage is increasing, especially in high performance networks.
Coaxial cabling is generally used for cable Internet access. We will
explain all three types of cabling. We will also explain a difference
between a straight-through and crossover cable.
Coaxial cabling
Coaxial
cable has an inner conductor that runs down the middle of the cable.
The conductor is surrounded by a layer of insulation which is then
surrounded by another conducting shield, which makes this type of
cabling resistant to the outside interference. This type of cabling
comes in two types, thinnet and thicknet. Both types have a maximum
transmission speed of 10 Mbps. Coaxial cabling was used for computer
networks, but today are largely replaced by twisted-pair cabling (Photo
credit: Wikipedia)
Twisted-pair cabling
A
twisted-pair cable has four pair of wires. These wires are twisted
around each other to reduce crosstalk and outside interference. This
type of cabling is common in most current LANs.
Twisted-pair
cabling can be used for telephone and network cabling. It comes in two
versions, UTP (Unshielded Twisted-Pair) and STP (Shielded Twisted-Pair).
The difference between these two is that an STP cable has an additional
layer of insulation that protects data from outside interferences.
Here you can see how a twisted pair cable looks like (Photo credit: Wikipedia):
A twisted-pair cable uses 8P8C connector, sometimes wrongly referred to as RJ45 connector (Photo credit: Wikipedia).
Fiber-optic cabling
This
type of cabling uses optical fibers to transmit data in the form of
light signals. The cables have strands of glass surrounded by a cladding
material (Photo credit: Wikipedia).
This
type of cabling can support greater cable lengths than any other
cabling type (up to a couple of miles). The cables are also immune to
electromagnetic interference. As you can see, this cabling method has
many advantages over other methods but it's drawback is that it is the
most expensive type of cabling.
There are two types of fiber-optic cables:
• Single-mode fiber (SMF) - uses only a single ray of light to carry data
• Multi-mode fiber (MMF) - uses multiple rays of light to carry data
• Multi-mode fiber (MMF) - uses multiple rays of light to carry data
Two types of connectors are commonly used:
• ST (Straight-tip connector)
• SC (Subscriber connector)
• ST (Straight-tip connector)
• SC (Subscriber connector)
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