Basic_Computer_Network_1_Semesterdfsfdsfs

computer networking basics

1. BASIC COMPUTER NETWORK 1
Prepared by Engr.
Engr.Exequiel M. Sabater,
CCPE

2. INTRODUCTION
TO COMPUTER
NETWORKS
Definition &
Purpose
Network
applications in
daily life
Components of a
network

3. INTRODUCTION
TO COMPUTER
NETWORKS
A computer network is basically a collection of
devices—like computers, servers, switches, routers,
and even smartphones—that are connected together
so they can communicate and share resources.
These devices communicate through protocols—like
TCP/IP—which act like a common language.
A network can be wired using cables, wireless using
Wi-Fi, or a combination of both.

4. INTRODUCTION
TO COMPUTER
NETWORKS
When we talk about a computer network, it’s not just
“computers” anymore—it includes phones, tablets,
printers, servers, and more.
Protocols like TCP/IP are the “languages” devices
use to understand each other.
The connection could be with cables, wireless signals,
or even fiber optics.

5. INTRODUCTION
TO COMPUTER
NETWORKS
A computer network is basically a collection of
devices—like computers, servers, switches, routers,
and even smartphones—that are connected together
so they can communicate and share resources.
These devices communicate through protocols—like
TCP/IP—which act like a common language.
A network can be wired using cables, wireless using
Wi-Fi, or a combination of both.

6. NETWORK
TYPES
LAN, MAN, WAN
PAN, WLAN
Advantages &
disadvantages

7. NETWORK
TYPES
•LAN (Local Area Network):
•A network that connects devices
(such as computers, printers, etc.)
within a small geographical area, like a home,
office, or building.
•Typically, LANs have high data transfer rates
and use technologies such as Ethernet or Wi-Fi.
•MAN (Metropolitan Area Network):
•A network that covers a larger geographical
area than a LAN, typically spanning a city or a
large campus.
•MANs are often used by businesses or
organizations to connect multiple LANs within a
city or town.
•WAN (Wide Area Network):
•A network that covers a large geographical area,
such as a country or even multiple countries.
•WANs connect multiple LANs and MANs, and
are usually established using public or private
data links like leased lines, satellites, or the
internet.

8. NETWORK
TYPES
•PAN (Personal Area Network):
•A network designed for personal use, typically
connecting devices such as smartphones,
tablets, laptops, and other personal gadgets
within a very small range (usually up to 10
meters).
•It allows the devices to communicate with each
other wirelessly, often using Bluetooth, infrared,
or other short-range technologies.
•WLAN (Wireless Local Area Network):
•A type of LAN that uses wireless
communication, typically Wi-Fi, to connect
devices within a limited area like a home, office,
or campus.
•WLAN allows devices to communicate without
the need for physical cables, providing mobility
within the covered area while maintaining high
data transfer speeds.

9. NETWORK
TYPES
Let’s play with this topic…..

10. NETWORK
TOPOLOGIES
Bus, Star, Ring,
Mesh, Hybrid
Pros & cons of
each topology

11. NETWORK
TOPOLOGIES
Bus Topology:
In a bus topology, all devices are connected to a
single central cable (the "bus"). The data sent by one
device is broadcast to all others, and only the device
addressed will accept and process the data.
Star Topology:
In a star topology, all devices are connected to a
central device, typically a switch or hub. Each device
communicates with others through this central device.
Ring Topology:
In a ring topology, each device is connected to two
other devices, forming a closed loop or ring. Data
travels in one direction around the ring until it
reaches its destination.
Mesh Topology:
In a mesh topology, each device is connected to
every other device in the network. This creates
multiple paths for data to travel between devices.
Hybrid Topology:
A hybrid topologycombines two or more different
network topologies (such as star, bus, or ring) within
the same network. This is often done to meet specific
needs or overcome limitations of individual
topologies.

12. NETWORK
TOPOLOGIES
Bus Topology
Pros:
Cost-Effective: Simple and inexpensive to
implement as it requires only a single central
cable (the bus).
Easy to Install: Suitable for small networks with
limited devices.
Minimal Cabling: Requires less cable compared
to star or mesh topologies.
Cons:
Single Point of Failure: If the main cable fails,
the entire network goes down.
Performance Issues: Data collisions can occur,
leading to slower speeds as more devices are
added.
Troubleshooting Difficulties: Identifying faults in
the bus can be complex, especially with larger
networks.

13. NETWORK
TOPOLOGIES
Star Topology
Pros:
Easy to Troubleshoot: Centralized management
makes it easier to detect and isolate issues.
Device Independence: Failure of one device
doesn’t affect others on the network.
Scalable: New devices can be easily added by
connecting to the central hub/switch.
Cons:
Single Point of Failure: The central hub or switch
is a critical point; if it fails, the entire network is
affected.
More Cabling: Requires more cables than bus
topology, which can increase cost in larger
networks.
Dependence on Central Hub: If the hub/switch
becomes overloaded, it can reduce network
performance.

14. NETWORK
TOPOLOGIES
Ring Topology
Pros:
Efficient Data Transfer: Data travels in a
unidirectional (or bidirectional) manner, reducing
collisions.
Simple Setup: It is easy to set up and manage in
smaller networks.
Predictable Network Performance: Each device
gets a fair share of the bandwidth in the network.
Cons:
Failure of One Device: If one device or
connection fails, it can break the entire ring unless
redundancy is added.
Difficult Troubleshooting: Identifying where the
failure occurred in the network is hard.
Slower Data Transfer: Performance can decrease
as the network grows, as data must pass through
multiple devices.

15. NETWORK
TOPOLOGIES
Mesh Topology
Pros:
Highly Reliable: Redundant connections ensure
continuous operation even if one link fails.
No Data Collisions: Since each device is
connected to every other device, there is no
contention for data transmission paths.
Scalable: Adding new devices doesn’t impact the
existing network significantly.
Cons:
High Cost: Requires a lot of cables and network
devices, making it expensive to implement.
Complex Setup: Configuring the network can be
difficult, especially as the number of devices
increases.
Difficult Maintenance: Managing and
troubleshooting a large mesh network can be
complex due to the number of connections.

16. NETWORK
TOPOLOGIES
Hybrid Topology
Pros:
Flexibility: Combines the strengths of multiple
topologies, offering a customized solution.
Scalable: Easily accommodates growth by
integrating different topologies as needed.
Fault Tolerance: Redundant systems can be built
into the network for added reliability.
Cons:
Complex to Implement: Designing and
maintaining a hybrid network can be more
complicated.
Expensive: The need for multiple types of
equipment and more cabling can increase costs.
Maintenance Challenges: Requires specialized
knowledge to manage and troubleshoot multiple
topologies within the same network.

17. NETWORK
DEVICES
Hub, Switch,
Router, Access
Point
NIC, Modem,
Firewall

18. NETWORK
DEVICES
Hub:
A hubis a basic networking device that connects
multiple devices in a network, typically using Ethernet
cables. It broadcasts data to all connected devices,
without any filtering or routing.
Function: A hub receives data from one device and
sends it to all other devices on the network
(broadcasting). It doesn't know the destination of the
data.
Usage: Used in older networks but has largely been
replaced by switches.
Router:
A routeris a device that connects different networks,
such as a local area network (LAN) to a wide area
network (WAN) or the internet. It routes data between
networks and determines the best path for data
transmission.
Function: A router inspects the destination IP address in
data packets and forwards them to the correct network.
It also assigns local IP addresses in a home network.
Usage: Essential for internet connectivity in homes and
businesses by routing data to and from the internet.

19. NETWORK
DEVICES
Switch:
A switchis a more advanced networking device
compared to a hub. It connects multiple devices within a
network and selectively forwards data only to the
specific device for which it is intended.
Function: A switch uses MAC addresses to forward data
packets to the correct device, improving network
efficiency compared to a hub.
Usage: Commonly used in modern LANs to reduce
congestion and enhance performance.
Access Point (AP):
An access pointis a device that allows wireless devices
(like laptops, smartphones, etc.) to connect to a wired
network (typically a LAN). It acts as a bridge between
wired and wireless networks.
Function: It connects wireless devices to a wired
network, extending the network’s range by transmitting
radio signals. Access points can also serve as a point to
manage and monitor wireless network traffic.
Usage: Commonly used in Wi-Fi networks to provide
wireless access to users within a defined range.

20. CABLING &
MEDIA
Twisted Pair,
Coaxial, Fiber
Optic
Wireless
transmission
basics

21. CABLING &
MEDIA
Twisted Pair Cable:
Definition: A twisted paircable consists of pairs
of insulated copper wires twisted together. It is
commonly used for telecommunication and
networking.
Types:
Unshielded Twisted Pair (UTP): No extra shielding around
the wires. It is widely used in Ethernet networks.
Shielded Twisted Pair (STP): Includes shielding around the
wire pairs to protect against electromagnetic interference.
Usage: Often used in local area networks (LANs),
telephone lines, and internet connections.
Pros:
Inexpensive and easy to install.
Flexible and suitable for shorter distances.
Cons:
Limited range (distance).
Susceptible to interference and signal degradation over
long distances.

22. CABLING &
MEDIA
Twisted Pair Cable:
Definition: A twisted paircable consists of pairs
of insulated copper wires twisted together. It is
commonly used for telecommunication and
networking.
Types:
Unshielded Twisted Pair (UTP): No extra shielding around
the wires. It is widely used in Ethernet networks.
Shielded Twisted Pair (STP): Includes shielding around the
wire pairs to protect against electromagnetic interference.
Usage: Often used in local area networks (LANs),
telephone lines, and internet connections.
Pros:
Inexpensive and easy to install.
Flexible and suitable for shorter distances.
Cons:
Limited range (distance).
Susceptible to interference and signal degradation over
long distances.

23. CABLING &
MEDIA
Coaxial Cable:
Definition: A coaxialcable consists of a central
conductor (usually copper) surrounded by an
insulating layer, a metal shield, and an outer
insulating cover.
Usage: Commonly used for cable television (TV)
connections, broadband internet, and some
network connections.
Pros:
Good resistance to electromagnetic interference due to the
shielding.
Can transmit data over longer distances compared to
twisted pair cables.
Cons:
Bulkier and less flexible than twisted pair cables.
More expensive than twisted pair cables.

24. CABLING &
MEDIA
Coaxial Cable:
Definition: A coaxialcable consists of a central
conductor (usually copper) surrounded by an
insulating layer, a metal shield, and an outer
insulating cover.
Usage: Commonly used for cable television (TV)
connections, broadband internet, and some
network connections.
Pros:
Good resistance to electromagnetic interference due to the
shielding.
Can transmit data over longer distances compared to
twisted pair cables.
Cons:
Bulkier and less flexible than twisted pair cables.
More expensive than twisted pair cables.

25. CABLING &
MEDIA
Fiber Optic Cable:
Definition: Fiber opticcables use strands of glass
or plastic to transmit data as light signals. The core
of the cable carries light signals, while layers of
cladding and protective coatings prevent loss of
light and signal interference.
Types:
Single-mode fiber: Carries light in a single path, used for long-
distance communication.
Multi-mode fiber: Carries light in multiple paths, used for
shorter distances.
Usage: Used for high-speed internet, long-distance
telecommunications, and high-performance
networks.
Pros:
Extremely high data transfer rates and bandwidth.
Immune to electromagnetic interference.
Can transmit data over very long distances without significant
signal loss.
Cons:
Expensive and more fragile than copper cables.
Requires specialized equipment for installation and
maintenance.

26. CABLING &
MEDIA
Fiber Optic Cable:
Definition: Fiber opticcables use strands of glass
or plastic to transmit data as light signals. The core
of the cable carries light signals, while layers of
cladding and protective coatings prevent loss of
light and signal interference.
Types:
Single-mode fiber: Carries light in a single path, used for long-
distance communication.
Multi-mode fiber: Carries light in multiple paths, used for
shorter distances.
Usage: Used for high-speed internet, long-distance
telecommunications, and high-performance
networks.
Pros:
Extremely high data transfer rates and bandwidth.
Immune to electromagnetic interference.
Can transmit data over very long distances without significant
signal loss.
Cons:
Expensive and more fragile than copper cables.
Requires specialized equipment for installation and
maintenance.

27. THANK YOU
Prepared by Engr.
Exequiel M. Sabater, CCPE