Cables in Computer
Networks : Introduction
- Cables are the one
of the most important component in any network. Cables in computer networks
acts as the transmission medium through which data transmission takes place
from one node to other. The cables in computer networks are classified as
:
Cable Categorization : Computer
Networks
Cables In Computer
Networks : Twisted Pair Cables
- Two or more than two
insulated wires when twisted together forms twisted pair cables. These cable
can further be classified into two types based on their features and
usability.
- Un-Shielded
twisted pair(UTP).
- Shielded
Twisted Pair(STP).
A) Un-Shielded Twisted Pair(UTP)
- The most commonly
general purpose cables used in the computer networks world are un-shielded
twisted pair cable. They do not have any special coating or shield on the
upper layers which results in high electromagnetic interference and hence
named as un-shielded.
- Cables used for LANs
and Telephones are unshielded twisted pair cables.
- Because of cheap
nature, easy installation and maintenance, they have high
demands.
- Unshielded twisted
pair cables are used for voice and data transmission single
handed-ly.
- Copper is used for
making UTP cables.
B) Shielded Twisted Pair(STP)
- The basic difference
between UTP and STP is, shielded twisted pair cables contains a special
coating on the top of the wire. This coating prevents leakage of
electromagnetic interference which results in high data transmission
speeds.
- These cables are
laid under the ground and are difficult to maintain.
- This leads to higher
installation cost and maintenance cost.
- Copper is used for
making STP cables.
Cables In Computer
Networks : Co-Axial Cables
- Co-axial cables has
lesser electromagnetic interference because of its double coating on over
the core of the cable. Thus, resulting in higher bandwidth and less data
losses.
- Co-axial cables are
also called as radio guided cables i.e. RG-59
cables.
- These cables are
much thicker than twisted pair cables having a diameter of range “0.4 to 1” inch.
- Copper is used for
making Co-Axial cables.
- Long distance
telephone lines is the example of co-axial cables.
Cables In Computer
Networks : Optical Fiber
- Optical Fibers are
commonly known as backbone cables. They have the highest bandwidth among all
the types of cables available.
- Optical Fibers are
made by combining glass and plastic together which results in a durable,
flexible and cylindrical cables.
- Because of their
glass and plastic architecture, they are quite thin and
sensitive.
- Optical fibers can
be divided into three major parts:
- Core : The center most part.
- Cladding : layer on an optical fiber which ensures that no two individual cables
comes in a direct contact.
- Jacket : Outermost covering over the optical fiber.
- The concept of optical
fiber is
based upon “Total Internal Reflection”. Thus, data travels in the form of light with the speed
of light forming a zigzag pattern inside the optical fiber.
Features of
Optical Fibers
- They have wider
temperature range i.e. they does not break or lose shape whenever
temperature changes.
- As plastic and glass are used to make optical
fibers, EMF does not have any effect on it.
- No short
circuits.
- Data transmission
over a long distance can be done without regenerating the
signals.
- Optical Fibers are
highly expensive and are not used in small organisations.
Cables In Computer
Networks : Comparison Among Specifications of Cables
Cable
Comparison : Computer Networks