Computer Networks Cont’d – Basic 6 Basic Technology Lesson Note (Second Term)

Learning Objectives

By the end of the lesson, pupils should be able to:

1. Define computer network
2. Define network technology
3. Outline types of network technology/topology

Content

Network Technology

Definition: Network technology refers to the methods, protocols, hardware, and software used to connect computers and devices to enable communication and resource sharing.

Components of Network Technology:

1. HARDWARE:

• Network Interface Cards (NICs)
• Switches
• Routers
• Hubs
• Cables (Ethernet, Fiber optic)
• Wireless Access Points
• Modems

2. SOFTWARE:

• Network Operating Systems
• Protocols (TCP/IP, HTTP, FTP)
• Network management software
• Security software (Firewalls)

3. TRANSMISSION MEDIA:

Wired:

• Twisted Pair Cable:
  1. Cat5e, Cat6, Cat7
  2. Most common
  3. Inexpensive
  4. Good for short/medium distances
• Coaxial Cable:
  1. Cable TV and older networks
  2. Better shielding than twisted pair
• Fiber Optic Cable:
  1. Uses light signals
  2. Very fast (up to 100 Gbps)
  3. Long distances
  4. Expensive
  5. Immune to electromagnetic interference

Wireless:

• Wi-Fi (Wireless Fidelity)
• Bluetooth
• Infrared
• Satellite
• Microwave
• Radio waves

Network Protocols

Definition: Rules and standards that govern how data is transmitted over networks.

Common Protocols:

1. TCP/IP – Transmission Control Protocol/Internet Protocol
2. HTTP/HTTPS – Web browsing
3. FTP – File transfer
4. SMTP – Email sending
5. POP3/IMAP – Email receiving
6. DNS – Domain name system

Network Security

Threats:

• Viruses and malware
• Hacking
• Unauthorized access
• Data theft
• Phishing

Protection:

• Firewalls
• Antivirus software
• Encryption
• Strong passwords
• Regular updates
• User authentication
• Network monitoring

Recap: Network Topologies

Types (Detailed):

1. Bus Topology

• Single cable backbone
• All devices connected
• Economical but less reliable

2. Ring Topology

• Circular connection
• Data travels one direction