Coaxial Cable
Coaxial cable is braided-grounded
strands of wire that can provide some shielding and noise immunity;
however, the installation and the termination of the cable itself can
be costly. Coaxial cabling, which uses connectors called BNC (Bayonet
Nut Connector) is known as, in forms of Ethernet, thicknet and thinnet,
in the older LAN technology, ARCnet, and cable TV.
Cat 3 UTP and STP
Category 3 UTP and STP (Cat 3) include
applications as voice (telephony) or data (up to 10 Mbps). More
commonly Cat 3 is used on a networks for cable segments to
workstations or printers. Cat 3 is not recommended for data
installations since its maximum bandwidth of 10Mbps is rapidly being
exceeded by many LAN technologies.
Category 5 UTP and STP
Applications for Category 5 UTP and STP
include voice (telephony) or data (up to 100 Mbps, or with certain
technologies, 1000 Mbps). Cat 5 is sometimes used as a backbone;
however is restricted to 100 meters in length. It is currently the
most popular cabling for connecting workstations and horizontal cable
runs due to its low cost, high bandwidth, relative ease of
installation, and ease of termination with RJ-45 connectors.
Fiber Optic 
Fiber optic cabling carries signals,
which have been converted from electrical to optical (pulses of light)
form. It consists of the core, either an extremely thin cylinder of
glass or optical quality plastic, which is surrounded by a second
glass or plastic layer called the cladding. The interface between the
core and cladding can trap light signals by a process called Total
Internal Reflection (TIR), resulting in the optical fiber acting as a
light pipe. Protective buffer and jackets materials are used to cover
the cladding layer. This type of cabling is less frequently used
because it is somewhat more expensive; however, it is rapidly
decreasing in both raw cost and installed cost.
Fiber optic cables are not susceptible
to interference, such as radio waves, fluorescent lighting, or any
other source of electrical noise. It is the common cable used for
network backbones and can support up to 1000 stations, carrying
signals beyond 25 km. Fiber terminations include SC, ST, and a variety
of proprietary connectors. Maximum data transfer rate is virtually
limitless: tens and hundreds of gigabits per second, limited only by
the electronics on each end of the fiber.
Unshielded Twisted Pair (UTP) 
Unshielded Twisted Pair (UTP) is a set
of three or four pairs of wires with each wire in each pair twisted
around the other to prevent electromagnetic interference. UTP cabling
uses RJ-45, RJ-11, RS-232, and RS-449 connectors. Because it is less
expensive and easier to install, UTP is more popular than Shielded
Twisted Pair (STP) or Coaxial Cabling. An example of UTP application
is telephone networks, which use RJ-11 connectors, and 10BASE-T
networks, which use RJ-45 connectors. UTP comes in the form of Cat 2,
3, 4, and 5 grades; however, only Cat 5 is now recommended for any
data applications. The maximum length is 100 meters, without using any
kind of signal regeneration device, and a maximum data transfer rate
of 1000 Mbps for Gigabit Ethernet.
Shielded Twisted Pair (STP) 
Shielded Twisted Pair (STP), like UTP,
also has four pairs of wires with each wire in each pair twisted
together. However, the difference is that STP is surrounded with a
foil shield and copper braided around the wires that allows more
protection from any external electromagnetic interference. Because of
the shielding, the cable is physically larger, more difficult to
install and terminate, and more expensive than UTP. For applications
in electrically noisy environments, STP uses RJ-45, RJ-11, RS-232, and
RS-449 connectors. Like UTP, STP also comes in Cat 2, 3, 4, or 5
grades; however, only Cat 5 is recommended for any data applications. The maximum cable length with no signal regenerating device is 100 meters, with a maximum data transfer rate is 500 Mbps.
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