Types of Cables used in Networking

Subject: Types of Cables used in Networking Mon Aug 13, 2012 1:32 pm

Types of Cables used in Networking:
Straight cable
This is the simplest type of cable. It consists of copper wires
surrounded by an insulator. The wire comes in bundles or as flat
"ribbon" cables and is used to connect various peripheral devices over
short distances. Cables for internal disk drives are typically flat
cables with multiple transmission wires running in parallel.

Twisted-pair cable

This cable consists of copper-core wires surrounded by an
insulator. Two wires are twisted together to form a pair, and the pair
forms a balanced circuit (voltages in each pair have the same amplitude
but are opposite in phase). The twisting protects against EMI
(electromagnetic interference) and RFI (radio frequency interference). A
typical cable has multiple twisted pairs, each color-coded to
differentiate it from other pairs. UTP (unshielded twisted-pair) has
been used in the telephone network and is commonly used for data
networking in the United States. STP (shielded twisted-pair) cable has a
foil shield around the wire pairs in a cable to provide superior
immunity to RFI. Traditional twisted-pair LANs use two pairs, one for
transmit and one for receive, but newer Gigabit Ethernet networks use
four pairs to transmit and receive simultaneously. UTP and STP are
constructed of 100-ohm, 24-AWG solid conductors.

Coaxial cable
This cable consists of a solid copper core surrounded by an
insulator, a combination shield and ground wire, and an outer protective
jacket. In the early days of LANs, coaxial cable was used for its high
bit rates. An Ethernet Thinnet (10Base-2) network has a data rate of
10Mbits/sec and implements a bus topology in which each station is
attached to a single strand of cable. Today, hierarchical wiring schemes
are considered more practical, and even though more twisted pair wire
is required to cable such a network, cost has dropped, making such
networks very practical.

Fiber-optic cable

This cable consists of a center glass core through which light waves
propagate. This core is surrounded by a glass cladding that basically
reflects the inner light of the core back into the core. A thick plastic
outer jacket surrounds this assembly, along with special fibers to add
strength. Fiber-optic cable is available with a metal core for strength
if the cable will be hung over distances.