Classroom Notes: 3.1 Types of Network

A standalone computer works entirely on its own. It is not connected to any other computers or internet.

A computer network is a collection of two or more computers and devices (smartphone, TAB, or printer) connected together so they can communicate with each other and share information.

Here are the main benefits of a computer network:

• Resource Sharing – Multiple people can use the same hardware (like printer, scanner, storage or software) saving money.
• Information Sharing – You can send documents, images, and videos to other information instantly without needing a USB drive.
• Better Communication – It allows for instant messaging, emails, and video calls.

A network needs three main ingredients to work: Hardware, Software, and Protocols.

• Network Hardware – The physical pieces you can touch. This includes the computers themselves, cables, and devices like Routers and Switches.
• Network Software – The programs that help run the computer network. This includes network operating systems that manage data security, user permissions, and traffic control.
• Protocols – The rules of the network. Computers need protocols (like HTTP for websites, TCP/IP for LAN and WAN) so they know exactly how to package and send data correctly.

A switch connects multiple devices (like computers, printers, and servers) together within the same local area network - LAN. Its main function is to receive data from one device and forward it directly to the specific destination device in the same network.

A router connects different networks to one another. Its main function is to forward data between your local network and outside networks, most notably connecting your home or school network to the Internet. It determines the best and fastest path for data to travel across the globe.

Networks are grouped by how much geographic space they cover (PAN, LAN, and WAN):

• Personal Area Network (PAN)
  • Description: A PAN is the smallest type of network, centered around a single person in a very small space (usually within 10 meters).
  • Example: Connecting your smartphone to your wireless headphones, or syncing a smartwatch to your phone.
• Local Area Network (LAN)
  • Description: A LAN connects computers within a limited, localized area, like a single building or a campus. It is fast and secure.
  • Example: Your school's computer lab, or an office building.
• Wide Area Network (WAN)
  • Description: A WAN covers a massive geographic area, such as a city, a country, or even the entire planet. It connects multiple smaller LANs together.
  • Example: The Internet is the largest and most famous WAN in the world.

To send data, devices must be connected either physically (cables) or through the air (radio waves). Wired Connections:

• Copper Cables (Ethernet) – Uses electrical signals to send data through copper wires. It is common, affordable, and great for local area networks (LAN).
• Fiber-Optic Cables – Uses pulses of light traveling through tiny strands of glass or plastic. It is incredibly fast and can carry data across oceans without losing strength, making it great for WAN.

Wireless Connections:

• Bluetooth – A short-range technology which uses radio waves to connect personal devices (like mice, keyboards, or speakers) without wires. Operates in the 2.402–2.480 GHz range.
• Wi-Fi – Uses radio waves to provide high-speed internet and network access within a specific area (like your school or home). Operates in the 2.4 GHz, 5 GHz, and 6 GHz ranges.
• Cellular – Uses a network of towers to provide internet access over wide areas to mobile devices (like 4G or 5G on your smartphone).