IP Addresses

🌐 Everything You Need to Know About IP Addresses

In the digital world, IP addresses (Internet Protocol addresses) play a crucial role in enabling communication between devices on a network. Whether you're browsing a website, sending an email, or streaming a video, IP addresses are working silently in the background.

This article covers:

  • What IP addresses are and why we use them

  • The different types of IP addresses

  • IP Address Classes

  • How IP addresses are structured

  • The difference between private and public IP addresses

  • What Is ifconfig

📌 What Is an IP Address and Why Do We Use It?

An IP address is a unique identifier assigned to each device connected to a network. It allows devices to find and communicate with each other over the internet or a local network.

Main purposes of IP addresses:

  • Device identification

  • Routing and delivering data between devices

  • Managing communication between clients and servers

Without IP addresses, it would be impossible to send data to the correct destination.

🧾 Types of IP Addresses

There are two major versions of IP addresses in use today:

1. IPv4 (Internet Protocol version 4)

  • Uses 32-bit addressing

  • Written in dot-decimal format (e.g., 192.168.1.1)

  • Supports about 4.3 billion unique addresses

2. IPv6 (Internet Protocol version 6)

  • Uses 128-bit addressing

  • Written in hexadecimal format separated by colons (e.g., 2001:0db8:85a3:0000:0000:8a2e:0370:7334)

  • Designed to handle a vastly larger number of devices (essential for IoT and future internet growth)

📊 IP Address Classes Table

Class

IP Range

First Octet Range

Default Subnet Mask

Hosts per Network

Purpose / Usage

A

1.0.0.0 – 126.255.255.255

1 – 126

255.0.0.0 (/8)

~16 million

Very large networks (ISPs, etc.)

B

128.0.0.0 – 191.255.255.255

128 – 191

255.255.0.0 (/16)

~65,000

Medium-sized networks

C

192.0.0.0 – 223.255.255.255

192 – 223

255.255.255.0 (/24)

254

Small networks

D

224.0.0.0 – 239.255.255.255

224 – 239

N/A

N/A

Multicast addressing

E

240.0.0.0 – 255.255.255.255

240 – 255

N/A

N/A

Experimental / Reserved

🛠️ How IP Addresses Are Structured

IPv4 Structure:

  • Composed of 4 decimal numbers (octets) ranging from 0 to 255

  • Example: 192.168.0.1

  • Each part represents 8 bits (4 x 8 = 32 bits)

IPv6 Structure:

  • Consists of 8 groups of 4 hexadecimal digits

  • Example:fe80::1ff:fe23:4567:890a

  • Offers 340 undecillion unique addresses (more than enough for every device on Earth)

🌍 Public vs. Private IP Addresses

Feature
Public IP Address
Private IP Address

Usage

For internet-wide communication

For local/internal network use

Assigned by

Internet Service Provider (ISP)

Local router or network administrator

Example

203.115.75.90

192.168.1.1, 10.0.0.2

Internet Access

Yes

No (unless via NAT)

Address Range

Globally unique

Limited to specific IP ranges

Private IP ranges:

  • 10.0.0.0 – 10.255.255.255

  • 172.16.0.0 – 172.31.255.255

  • 192.168.0.0 – 192.168.255.255

Private IP addresses are not routable over the public internet. Instead, they’re used internally within homes, offices, or corporate networks. To communicate outside, they’re translated into public IPs using NAT (Network Address Translation).

🔧 What Is ifconfig?

ifconfig Stands for interface configuration. It allows you to:

  • View network interface details

  • Assign IP addresses to interfaces

  • Enable or disable interfaces

  • Set subnet masks, broadcast addresses, etc.

In Linux (Using ifconfig)

View All Network Interfaces:

ifconfig

In Windows (Using Command Prompt or PowerShell)

View Network Configuration:

ipconfig

View Full Details:

ipconfig /all
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