Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.
What is a computer network?
A network connects several nodes or networking
devices together. This allows sharing of
resour...
Different Types of Networks
• LAN (Local Area Network)
Also includes WLAN (Wireless LAN)
• WAN
• MAN
In this presentation ...
LAN (Local Area Network)
• It is a small network with a maximum coverage
of about a few buildings.
• Allows sharing of pri...
Topologies of LAN
• Bus Topology
• Ring Topology
• Star Topology
Bus Topology
Computers are connected to a
main line
Data moves towards the
destination node
A Terminator is often used
her...
(continued)
Advantages: easy to add new
node, entire network will not get
affected with the failure of one
node, less cabl...
Ring Topology
It’s a chain of nodes
cabled together to form
a loop/ring.
Each computer receives
data only relevant to it a...
(continued)
Advantages: functions
efficiently even with
heavy data load, suitable
for larger networks.
Disadvantages: netw...
Star Topology
Each node is connected to
each other by a hub or a
switch.
Every node has its own
connection to the hub.
Adv...
WAN(Wide Area Network)
A network over a large area such as
cities, countries, etc.
Connected by a router or a modem
Expens...
WLAN (Wireless Local Area Network)
Communication is made over short distances with either
radio or infrared signals instea...
Network Devices
Modem (Modulator Demodulator): converts digital signals
in to analogue signals (modulation) and vice versa...
THANK YOU!
Computer Networks
Upcoming SlideShare
Loading in …5
×

Computer Networks

1,065 views

Published on

This the ppt I made for my ICT formatives. I hope you'll like it!

Published in: Education, Technology, Business
  • Be the first to comment

Computer Networks

  1. 1. What is a computer network? A network connects several nodes or networking devices together. This allows sharing of resources such as printers, storage memory, etc.
  2. 2. Different Types of Networks • LAN (Local Area Network) Also includes WLAN (Wireless LAN) • WAN • MAN In this presentation we will only be looking at LAN, WAN and WLAN.
  3. 3. LAN (Local Area Network) • It is a small network with a maximum coverage of about a few buildings. • Allows sharing of printers, medium sized files, etc. • Mainly used in offices and schools. • Advantages: sharing of resources, communication increases, controlled by an administrator. • Disadvantages: malware threat, queues, slower access to external networks, lesser data security compared to stand alone computers, if there is a break-down of a node then the network will brake.
  4. 4. Topologies of LAN • Bus Topology • Ring Topology • Star Topology
  5. 5. Bus Topology Computers are connected to a main line Data moves towards the destination node A Terminator is often used here. It is a device used at the ends of the main line to avoid signal bounce which can lead to data interference.
  6. 6. (continued) Advantages: easy to add new node, entire network will not get affected with the failure of one node, less cables required, cost efficient. Disadvantages: if main line malfunctions the entire network will fail, more nodes will decrease speed, difficult to isolate a fault on a particular device or computer.
  7. 7. Ring Topology It’s a chain of nodes cabled together to form a loop/ring. Each computer receives data only relevant to it as each computer has a unique identification number.
  8. 8. (continued) Advantages: functions efficiently even with heavy data load, suitable for larger networks. Disadvantages: networks can fail of there is a cable fault, addition of new node is difficult as it has to be placed between existing ones.
  9. 9. Star Topology Each node is connected to each other by a hub or a switch. Every node has its own connection to the hub. Advantages: if one node fails the entire network is not affected, easy to work on a faulty node and isolating it, network can be easily expanded Disadvantage: break down of hub will lead into full network crash Hub/Switch
  10. 10. WAN(Wide Area Network) A network over a large area such as cities, countries, etc. Connected by a router or a modem Expensive because of additional hardware and operating system E.g.: Internet
  11. 11. WLAN (Wireless Local Area Network) Communication is made over short distances with either radio or infrared signals instead of cables. Ranges of different signals • Radio: 30-50 metres • Infrared: 1-2 metres A device called Access Point is connected to such networks. Advantages: all computers can access that same material, less cabling, flexibility, adding new device is easy. Disadvantages: big security threat if network is unprotected, signals can be interfered with, transfer rate is less
  12. 12. Network Devices Modem (Modulator Demodulator): converts digital signals in to analogue signals (modulation) and vice versa (demodulation). Network Hub: connects numbers of nodes from where it receives of one device and sends it to all devices. Switches: connects numbers of nodes from where it receives data and sends it to the relevant node. Routers: used to connect networks together and to the Internet.
  13. 13. THANK YOU!

×