This document provides information about different types of transmission cables including coaxial cable, twisted pair cable, and fiber optic cable. It discusses the structure, types, applications and advantages/disadvantages of each cable. Coaxial cable transmits signals over larger distances at higher speeds compared to twisted pair. Twisted pair cables have two insulated copper wires twisted together to reduce electromagnetic interference. Fiber optic cables transmit data using light pulses through glass cores and have very high bandwidth and low susceptibility to interference.

1. Course Tittle: Computer Networks Lab
Course Code: CSE318
Topics: Wires &Cables
Submitted to:
Pranab Bandhu Nath
Senior Lecturer,Dept of CSE
City University, Dhaka.
Submitted By:
Name: Neheruma Sultana Riya
ID:1834902578
Dept: CSE(Day)
Batch:49th

2. Data transmission medium are two types: Guided Media & Unguided Media.
Guided Media are three types of cable. These are: Coaxial Cable, Twisted
Pair Cable & Fiber Optic Cable.
Coaxial Cable:
Coaxial cables, commonly called coax, are copper cables with metal shielding
designed to provide immunity against noise and greater bandwidth. Coax can
transmit signals over larger distances at a higher speed as compared to twisted pair
cables.
Coaxial cable is a type of cable that has an inner conductor surrounded by an
insulating layer, surrounded by a conductive shielding. Many also have an
insulating outer jacket Electrical signal flows through the center conductor. In
Center conductor it made with copper-clad steel. Center conductor bond is clean
stripping polymer is utilized to block moisture migration. a UV stable outer jacket
of either polyethylene (PE) or PVC is available to protect the core during
installation and for the installed life of the cable.

3. Coaxial cable types:
Coaxial cables are categorized into three types as per radio government (RG) ratings −
• RG – 59: Has impedance of 75W and used in cable TV.
• RG – 58: Has impedance of 50W and used in thin Ethernet.
• RG – 11: Has impedance of 50W and used in thick Ethernet.
• RG-6: Has impedance of 75W and used in video, tv.
Applications of Coaxial Cables:
1. In analog telephone networks: A single coaxial network can carry about
10,000 voice signals.
2. In digital telephone networks: A coax has a data rate of 600 Mbps.
3. In cable TV networks
4. In traditional Ethernet LANs
5. In MANs
6. Inexpensive
7. Easy to wire and install
8. Easy to expand
9. Good resistance to EMI
10.Durable.
Twisted Pair Cable:
Twisted pair cabling is a type of wiring in which two conductors of a single circuit
are twisted together for the purposes of improving electromagnetic compatibility.
One of the earliest guided transmission media is twisted pair cables. A twisted pair
cable comprises of two separate insulated copper wires, which are twisted together
and run in parallel. The copper wires are typically 1mm in diameter. One of the
wires is used to transmit data and the other is the ground reference. When the wires
are twisted, some part of the noise signals is in the direction of data signals while
the other parts are in the opposite directions. Thus, the external waves cancel out
due to the different twists. The receiver calculates the difference in the voltages of
the two wires for retrieving data. Thus, a much better immunity against noise is
obtained.

4. Types of Twisted Pair :
There are two types of twisted pairs are as follows: Unshielded twisted pair (UTP),
and shielded twisted pair (STP)
Unshielded Twisted Pair:
A twisted pair includes two insulated conductors twisted together in the spiral form, as
shown in the figure. It can be shielded with a plastic cover. The UTP cables are very low-
cost and simple to install.
Categories of UTP:
There are the following categories of the unshielded twisted pair cable −
Category5 − Its bandwidth is 100 MHz It can carry information at a rate of 100
Mbps. It can carry digital signals used for LANs.

5. Category6 − Its bandwidth is 200 MHz It can carry information at a rate of 200
Mbps. It is used for digital signal propagation in LANs.
Shielded Twisted Pair:
In this, each insulated twisted pair are shielded by a metal foil or braided mesh. This
mesh is also known as a metal shield. It decreases the interference of the disturbance
caused by the surrounding. This property makes the cable bulky and expensive.
Advantages of Twisted Pair Cables:
• It is easiest to install, manpower to repair, and service are readily available.
• In the mobile system, the signal can traverse various kilometers without
amplification.
• It can be the least costly for short distances.
• If part of a twisted-pair cable is broken, the whole network is not shut down.
• It is flexible and easy to connect.
• It has a low weight.
Disadvantages of Twisted Pair Cables:
• It is higher error rates when the line length is more than 100 meters because
it is easily affected by more signals.
• It has low bandwidth.
• It only supports a data transfer rate of up to 10 MBPS (Megabytes per
second).
Fiber-optic cable:
A fiber-optic cable, also known as an optical-fiber cable, is an assembly similar to
an electrical cable, but containing one or more optical fibers that are used to carry
light.

6. Structure:
A fiber optic cable has three parts −
• Core − It is the innermost portion of an optical fiber through which light
propagates. It is cylindrical in shape and it made up of a flexible glass of high
refractive index. The diameter of the core of a single mode fiber is 8 – 10 μm
while multimode fibers are 50 μm in diameter. It is also called the optical
waveguide since it is the main channel through which light signals are
transmitted.
• Cladding − The core is surrounded by a glass cladding. The glass of cladding
has a lower refractive index than the core. This enables total internal reflection
of light waves in the core, and eventually propagation of light waves within
the core.
• Outer Coating or Jacket − The outer jacket is a thin plastic sheath or coating
that is opaque to light. It prevents light rays from outside to enter the optical
fiber. Fibers are typically bundling together, where each bundle is covered by
a protective outer sheath that prevents the fibers from physical damage.
Types of Optical Fibers:
There are two types of fibers −
• Step-index fiber: In these, the refractive index of the core is constant and
undergoes an abrupt change at the interface with the cladding.
• Graded-index fiber: The refractive index of the core varies in a radial manner
from the center. The fiber is densest at the core and becomes rarer towards the
edge of the core.
Communication:
In fiber optic communication, data is transmitted from the source to the destination
by sending light pulses through optical fibers. It changes electrical pulses to light
signals and vice versa for communication. Fiber optic communications are preferred
when a huge amount of data needs to be transmitted across large distances.

7. The process of communication using fiber optics has the following steps −
• Conversion of input electrical data to light signals: The data to be sent by
the sender is in the form of electrical signals. These signals are converted to
light pulses by the transmitter circuitry using a light source. A light source is
of two types: LED and a laser diode.
• Transmission of light signals: The light signal is transmitted over a network
of optical fiber cables. During transmission, the signals should not become
too weak or distorted.
• Receiving of light signals: The receiver detects the light signals using a
photodetector that converts light pulses to electrical pulses. Photodetectors are
of two types: PN photodiode and avalanche photodiode.
Advantages of Fiber Optic Cables:
• Fiber cables offer several advantages over long-distance copper cabling.
• Fiber optics support a higher capacity. The amount of network bandwidth a
fiber cable can carry easily exceeds that of a copper cable with similar
thickness. Fiber cables rated at 10 Gbps, 40 Gbps, and 100 Gbps are
standard.
• Because light can travel for much longer distances over a fiber cable without
losing its strength, the need for signal boosters is lessened.
• A fiber optic cable is less susceptible to interference. A copper network
cable requires shielding to protect it from electromagnetic interference.
While this shielding helps, it is not sufficient to prevent interference when
many cables are strung together in proximity to one another. The physical
properties of fiber optic cables avoid most of these problems.
https://en.wikipedia.org/wiki/Fiber-optic_cable
https://www.tutorialspoint.com/Fiber-Optic-Communications
https://www.lifewire.com/fiber-optic-cable-817874
https://www.tutorialspoint.com/what-is-twisted-pair-cable
https://en.wikipedia.org/wiki/Twisted_pair

8. https://www.geeksforgeeks.org/advantages-and-disadvantages-of-twisted-
pair/
Reference: https://www.tutorialspoint.com/Coaxial-Cable
https://uk.rs-online.com/web/generalDisplay.html?id=ideas-and-advice/coaxial-cable-guide
https://www.ppc-online.com/blog/what-is-coaxial-cable-and-how-is-it-used