this power point is to make you learn more about the topic guided and unguided media in computer fundamentals and uses of these this will also help you to learn about different types of topology in computer and gain your knowledge of computer in many ways.

2. INDEX
 INTRODUCTION
 WHAT IS A GUIDED MEDIA
 TYPES OD GUIDED MEDIA
 PICTURE OF GUIDED MEDIA
 WHAT IS A UNGUIDED MEDIA
 PICTURE OF UNGUIDED MEDIA
 What is network tropology
 Types of tropology and uses.
 PICTURE OF DIFFERENT TROPOLOGY
 CONCLUSION
 BIBLOGAPHY

3. INTRODUCTION
With Guided media the waves are guided along a physical path
example of guided media includes telephone line, twisted pair
cables, coaxial cable, etc.
Unguided media are methods that allow the transmission of
data without the use of physical means to define the path it lack

4. WHAT IS A GUIDED MEDIA
GUIDED MEDIA are those that provide the conduit
from device to another include twisted pair cable,
telephone line, etc. It uses a cabling system that
guides a data signal along the specific path. The data
signal are bounded by the ‘cabling system’. It is also
known as the bound media. Cabling is meant in a
generic sense in the previous sentence and is not
meant to be interpreted as copper wire cable only.

5. WHAT IS A GUIDED MEDIA
Cable is medium through from which network
usually moves from one device to another.

6. TYPES OF GUIDED MEDIA
THERE ARE BASICALLY FOUR TYPES OF GUIDED MEDIA :
1- OPEN WIRE
2-TWISTED CABLE
3- FIBRES OPTICL CABLES
4- COAXIAL CABLES

7. 1. OPEN WIRE
Open Wire is traditionally used to describe the electrical wire
strung along power poles. There is a single wire strung between
poles. No shielding or protection from noise interference is used.
We are going to extend the traditional definition of Open Wire
to include any data signal path without shielding or protection
from noise interference. This can include multiconductor cables
or single wires. This media is susceptible to a large degree of
noise and interference and consequently not acceptable for data
transmission except for short distances under 20 ft.

8. 2. TWISTED CABLE
Twisted pair cable is least expensive and most widely used. The wires
in Twisted Pair cabling are twisted together in pairs. Each pair would
consist of a wire used for the data signal and a wire used for the
data signal. Any noise that appears on one wire of the pair would
occur on the other wire. Because the wires are opposite polarities,
they are 180 degrees out of phase When the noise appears on both
wires, it cancels or nulls itself out at the receiving end. Twisted Pair
cables are most effectively used in systems that use a balanced line
method of transmission : polar line coding (Manchester Encoding)
as opposed to unipolar line coding (TTL logic).

9. 3. FIBRES OPTICAL CABLES
Fiber-optic is a glass cabling media that sends network signals using
light. Fiber-optic cabling has higher bandwidth capacity than copper
cabling, and is used mainly for high-speednetwork Asynchronous
Transfer Mode (ATM) or Fiber Distributed Data Interface (FDDI)
backbones, long cable runs, and connections to high-performance
workstations. A fiber-optic cable is made of glass or plastic and
transmits signals in the form of light. Light is a form of
electromagnetic energy. It travels at its fastest in a vacuum: 3,00,000
kilometers/sec. The speed of light depends on the density of the
medium through, which it is traveling (the higher the density, the
slower the speed).

10. 3. FIBRES OPTICAL CABLES
Light travels in a straight line as long as it is moving through a
single uniform substance. If a ray of light traveling through one
substance suddenly enters another (more or less dense), the ray
changes direction. This change is called.
Refraction : The direction in which a light ray is refracted
depends on the change in density encountered. A beam of light
moving from a less dense into a denser medium is
bent towards vertical axis.

11. 4. COAXIAL CABLES
A form of network cabling used primarily in older Ethernet networks and in
electrically noisy industrial environments. The name “coax” comes from its two-
conductor construction in which the conductors run concentrically with each other
along the axis of the cable. Coaxial cabling has been largely replaced by twisted-
pair cabling for local area network (LAN) installations within buildings, and by
fiber-optic cabling for high-speed network backbones.
Coaxial cable (or coax) carries signals of higher frequency ranges than twisted-
pair cable. Instead of having two wires, coax has a central core conductor of solid
or standard wire (usually copper) enclosed in an insulating sheath, which is, in
turn, encased in an outer conductor of metal foil, braid, or a combination of the
two (also usually copper).

12. 4. COAXIAL CABLES
Coaxial cable (or coax) carries signals of higher frequency
ranges than twisted-pair cable. Instead of having two
wires, coax has a central core conductor of solid or
standard wire (usually copper) enclosed in an insulating
sheath, which is, in turn, encased in an outer conductor
of metal foil, braid, or a combination of the two (also
usually copper).

13. PICTURE OF GUIDED MEDIA

14. WHAT IS UNGUIDED MEDIA
A transmission medium is a material substance (solid, liquid,
gas, or plasma) that can propagate energy waves. For
example, the transmission medium for sounds is usually a gas,
but solids and liquids may also act as a transmission medium
for sound.
The absence of a material medium in vacuum may also
constitute a transmission medium for electromagnetic waves
such as light and radio waves. While material substance is not
required for electromagnetic waves to propagate, such waves
are usually affected by the transmission media they pass
through, for instance by absorption or by reflection or
refraction at the interfaces between media.

15. WHAT IS UNGUIDED MEDIA
The term transmission medium also refers to a technical
device that employs the material substance to transmit or
guide waves. Thus, an optical fiber or a copper cable is a
transmission medium. Not only this but also is able to
guide the transmission of networks.
A transmission medium can be classified as a:
Linear medium, if different waves at any particular
point in the medium can be superposed;
Bounded medium, if it is finite in extent, otherwise
unbounded medium;

16. WHAT IS UNGUIDED MEDIA
Uniform medium or homogeneous medium, if its
physical properties are unchanged at different
points;
Isotropic medium, if its physical properties are
the same in different directions.
Coaxial cable, one example of a transmission
medium

17. PICTURE OF UNGUIDED MEDIA

18. What is network tropology
The physical topology of a network refers to the
configuration of cables, computers, and other
peripherals. Physical topology should not be confused
with logical topology which is the method used to pass
information between workstations. Logical topology
was discussed in the Protocol chapter.
Main Types of Network Topologies In networking, the
term "topology" refers to the layout of connected
devices on a network. This article introduces the
standard topologies of computer networking.

19. WHAT IS NETWORK TROPOLOGY
One can think of a topology as a network's
virtual shape or structure. This shape does
not necessarily correspond to the actual
physical layout of the devices on the
network. For example, the computers on a
home LAN may be arranged in a circle in a
family room, but it would be highly unlikely to
find an actual ring topology there.

20. TYPES OF NETWORK TROPOLOGY
Network topologies are categorized into the
following basic types:
 Star Tropology
 Ring Tropology
 Bus Tropology
 Mesh Tropology

21. STAR TROPOLOGY
Many home networks use the star topology.
A star network features a central connection
point called a "hub" that may be a hub,
switch or router. Devices typically connect to
the hub with Unshielded Twisted Pair (UTP)
Ethernet.
Compared to the bus topology, a star
network generally requires more cable, but a
failure in any star network cable will only
take down one computer's network access
and not the entire LAN.

22. RING TROPOLOGY
In a ring network, every device has exactly
two neighbors for communication purposes.
All messages travel through a ring in the
same direction (either "clockwise" or
"counterclockwise"). A failure in any cable or
device breaks the loop and can take down
the entire network.
To implement a ring network, one typically
uses FDDI, SONET, or Token Ring
technology. Ring topologies are found in

23. BUS TROPOLOGY
Bus networks use a common backbone to connect
all devices. A single cable, the backbone functions
as a shared communication medium that devices
attach or tap into with an interface connector. A
device wanting to communicate with another device
on the network sends a broadcast message onto the
wire that all other devices see, but only the intended
recipient actually accepts and processes the
message.
Ethernet bus topologies are relatively easy to install
and don't require much cabling compared to the
alternatives. Ethernet cabling options many years
ago for bus topologies. However, bus networks work
best with a limited number of devices. If more than a
few dozen computers are added to a network bus,

24. MESH TROPOLOGY
involve the concept of routes. Unlike each
of the previous topologies, messages sent
on a mesh network can take any of several
possible paths from source to destination.
Some WANs, most notably the Internet,
employ mesh routing.
A mesh network in which every device
connects to every other is called a full mesh.
As shown in the illustration below, partial
mesh networks also exist in which some

25. PICTURE OF TYPES TROPOLOGIES

26. CONCLUSION
By making this project on the topic ‘ guided and
unguided media’ I let to know about the topic I
thank my sir ‘MR. RAVINDER’ to give me such
a wonderful project I want sir to give such
project again and again.
Your faithful
Prem kumar
Of class VIII ‘B’

27. bibliography
I have completed this project with the help
of internet, my computer book and mostly
under of guidance of my computer sir and
my respected parents.