Computer Networking Concept

Computer networking is a broad field, but this article is written to help you understand the core concepts in a simple way. We will cover topics such as: what is a computer network, types of computer networks, network topologies, transmission media, twisted pair standards, ethernet types, network protocols, and troubleshooting basics.

What is a Computer Network?

A computer network is a collection of hardware devices connected through a communication channel to share information and resources such as files, printers, or internet access.

Types of Computer Networks

1. LAN: Small area like home, school, or office.
2. MAN: Connects LANs within a city.
3. CAN: University, base, or campus network.
4. PAN: Personal devices (printer, phone, etc.).
5. WAN: Country or global coverage.
6. GAN: Global wireless + satellites.
7. Dial-Up: Phone lines + modem.
8. Wireless: WLAN, WMAN, WWAN.

Network Topology

Network topology refers to the physical arrangement of devices in a network.

• Star: All devices connect to a hub.
• Mesh: Every device connects to all others.
• Bus: Single backbone cable with terminators.
• Ring: Circular path, one-way data flow.
• Tree: Combination of star + bus.

Transmission Media

Transmission media are the channels through which data travels.

• Coaxial Cable – shielded, older LANs/TV.
• Fiber Optic – fast, immune to interference.
• Radio – Wi-Fi (802.11).
• Infrared – short-range, line-of-sight.
• Satellite – microwave signals via orbit.
• Twisted Pair – UTP/STP, most common.

Twisted Pair Standards

Type	Speed	Use
CAT1	1 Mbps	Telephone
CAT2	4 Mbps	Token Ring
CAT3	16 Mbps	Old Ethernet
CAT4	20 Mbps	Token Ring
CAT5	100 Mbps	LANs

Ethernet Types

Type	Speed	Cable
10BaseT	10 Mbps	Twisted Pair
10Base2	10 Mbps	Coax (Thin)
10Base5	10 Mbps	Coax (Thick)
10BaseF	10 Mbps	Fiber
100BaseT	100 Mbps	Twisted Pair

Network Protocols

• TCP/IP – Internet standard, scalable.
• NetBEUI – Simple, small LANs.
• IPX/SPX – Novell NetWare.

Network Troubleshooting

• Check cables + NIC lights
• Verify IP config
• Restart devices
• Replace faulty NICs

Data Loss Prevention

• Mirroring – live duplication
• Tape Backup – scheduled recovery
• Clustering – multiple servers for reliability