Basics of Networking
Welcome back to our networking basics series!
In this post, we’ll learn about the important network components, devices, and commands that help computers communicate with each other.
💡 What is a Network?
A network is simply a group of devices connected together so that they can communicate and share resources like files, printers, or the internet.
These devices can be:
- Computers
- Laptops
- Smartphones
- Routers
- Servers
A network can be as big as the Internet or as small as two computers at home sharing files or a printer.
When these devices are connected and share data, that’s called Networking.
⚙️ Components of a Network
🖥️ Personal Computer (PC)
Your computer or laptop acts as an endpoint — sending and receiving data over the network.
🔌 Network Interface Card (NIC)
- NIC is a small chip (or card) inside your computer’s motherboard.
- It connects your computer to the network.
- It has an RJ-45 port (for Ethernet cable) and a MAC address (unique ID assigned by the manufacturer).
🧵 Cables and Connectors
- These allow devices to connect and transfer data.
- RJ-45 connector – used for Ethernet cables
- RJ-11 connector – used for telephone lines
🧠 What is a Host?
A host is any device that has an IP address and connects to the network — for example:
- Computers
- Laptops
- Smartphones
- Network printers
Basically, if it can communicate online, it’s a host.
🔄 What is a Topology?
Topology describes how devices (hosts) are arranged and connected in a network.
Common types include:
- Star Topology – all devices connect to a central hub or switch
- Ring Topology – each device connects to two others, forming a ring
- Bus Topology – all devices share one main cable
- Mesh Topology – every device connects to every other device
- Hybrid Topology – a mix of two or more topologies
Modern networks mostly use star, mesh, or hybrid topologies.
📩 Message Types: Unicast, Multicast, and Broadcast
| Type | Description | Example |
|---|---|---|
| Unicast | One sender → One receiver | Sending a file to one computer |
| Multicast | One sender → Many receivers | Online video classes or webinars |
| Broadcast | One sender → All devices in the network | Sending an announcement to all |
🧭 Network Devices
🛣️ Router
- Connects two or more different networks
- Works on Layer 3 (Network Layer)
- Chooses the best path for data using a routing table
Example:
When you access a website, your router decides how your request travels through the internet.
🔌 Hub
- A Layer 1 (Physical Layer) device
- Connects multiple computers in a LAN
- Always broadcasts data to all devices
- Known as a dummy device
- Has fewer ports and no MAC learning ability
⚠️ Hubs are now obsolete (no longer used) because they are slow and inefficient.
🔄 Bridge
- Connects multiple hubs together in a network
- Helps to divide a large network into smaller parts
🔲 Switch
- Works on Layer 2 (Data Link Layer)
- Connects multiple computers in a LAN
- Learns MAC addresses and sends data only to the correct device
- Called an intelligent hub
Types of Switches:
- Manageable Switch – allows configuration and control
- Unmanageable Switch – plug and play, no configuration
Modern multi-layer switches can even work as routers.
Popular Brands: Cisco, Juniper, Huawei, HP, D-Link, TP-Link
🚪 What is a Gateway?
A Gateway is like the main entrance or exit of your network — usually your router.
All data going outside your LAN or coming inside passes through the gateway.
📶 What is a Modem?
Modem stands for Modulation and Demodulation.
It converts digital signals from your computer into analog signals for transmission — and vice versa.
- Sender side: Performs modulation (digital → analog)
- Receiver side: Performs demodulation (analog → digital)
This is how your internet connection works over telephone or cable lines.
🔁 What is a Repeater?
A Repeater is a Layer 1 device that boosts weak signals.
When data travels long distances, it may lose strength — a repeater amplifies the signal to its original strength.
📡 What is an Access Point (AP)?
An Access Point (AP) connects wireless devices (like phones or laptops) to a wired LAN.
It helps merge wireless and wired networks and extends Wi-Fi range.
🛰️ What is WLC?
WLC (Wireless LAN Controller) is used to manage multiple access points in large networks like offices or campuses.
🧰 Useful Network Commands (Windows)
| Command | Purpose |
|---|---|
| ping | Check if another device is reachable |
| ipconfig | View your IP address |
| ipconfig /all | View IP + MAC address |
| getmac | Show MAC address |
| netstat | Check active network connections |
| nslookup | Find DNS servers for a website |
| arp -a | View ARP table |
| arp -d | Delete ARP table (Admin mode) |
🔍 To check your public IP address, visit: www.whatismyipaddress.com
🖥️ How to Assign an IP Address to Your PC
- Press Windows + R
- Type
ncpa.cpl→ Press Enter - Right-click your LAN adapter → Choose Properties
- Click Internet Protocol Version 4 (TCP/IPv4) → Click Properties
- Select “Use the following IP address” and assign your IP manually.
✅ Summary
- A network connects multiple devices for sharing data.
- Routers, switches, and access points are key networking devices.
- Topologies define how devices are arranged.
- Commands help you check and troubleshoot network settings.
Networking is the backbone of our digital world — and understanding these basics will help you in any IT or cybersecurity journey