What is an IP Address? Full Deatils with suitable example

1. Introduction

An IP Address (Internet Protocol Address) is a unique numerical identifier assigned to each device connected to a computer network that uses the Internet Protocol (IP) for communication.

It acts like a home address for a computer or device on a network, allowing other devices to find and communicate with it over the internet or local network.

For example, when you visit a website like www.csaccept.com, your computer needs to know the IP address of the web server hosting that site to establish a connection.

2. Definition

An IP address is a numerical label assigned to each device (such as a computer, printer, or smartphone) connected to a network that uses the Internet Protocol for communication.

It serves two main purposes:

  1. Identification – Identifies the host or network interface.
  2. Location addressing – Provides the location of the device in the network.

3. Example of IP Address

Here are some common examples:

  • IPv4 Address: 192.168.1.1
  • IPv6 Address: 2001:0db8:85a3:0000:0000:8a2e:0370:7334

4. Types of IP Addresses

IP addresses can be classified in several ways:

A. Based on Version

There are two main versions of IP:

  1. IPv4 (Internet Protocol version 4)

  2. IPv6 (Internet Protocol version 6)

Let’s understand both in detail.

(i) IPv4 (Internet Protocol Version 4)

  • IPv4 is the fourth version of the Internet Protocol.
  • It uses a 32-bit address scheme, allowing around 4.3 billion unique addresses.
  • IPv4 addresses are represented in decimal format, separated by dots.

Example:

192.168.0.1

Structure:
Each IPv4 address is divided into 4 parts (called octets), e.g.,
192.168.0.1 → 192 | 168 | 0 | 1
Each octet can range from 0 to 255.

(ii) IPv6 (Internet Protocol Version 6)

  • IPv6 is the newest version developed to overcome IPv4 address exhaustion.
  • It uses a 128-bit address scheme, allowing a huge number of unique addresses.
  • IPv6 addresses are represented in hexadecimal format, separated by colons.

Example:

2001:0db8:85a3:0000:0000:8a2e:0370:7334

IPv6 also supports features like auto-configuration, enhanced security, and efficient routing.

B. Based on Use

  1. Private IP Address
    • Used within a private network (like home, school, or office).
    • Not directly accessible from the Internet.
    • Example: 192.168.1.5, 10.0.0.2
  2. Public IP Address
    • Assigned by an Internet Service Provider (ISP).
    • Used to identify a device on the Internet.
    • Example: 8.8.8.8 (Google’s Public DNS)

C. Based on Permanence

  1. Static IP Address
    • Does not change; permanently assigned to a device.
    • Commonly used for servers or hosting websites.
    • Example: 203.120.45.67
  2. Dynamic IP Address
    • Changes periodically; assigned temporarily by a DHCP server.
    • Common for home and mobile networks.

5. Classes of IPv4 Addresses

IPv4 addresses are divided into five classes based on their range:

Class Range Default Subnet Mask Usage
A 1.0.0.0 – 126.255.255.255 255.0.0.0 Very large networks
B 128.0.0.0 – 191.255.255.255 255.255.0.0 Medium-sized networks
C 192.0.0.0 – 223.255.255.255 255.255.255.0 Small networks
D 224.0.0.0 – 239.255.255.255 — Multicasting
E 240.0.0.0 – 255.255.255.255 — Research and development

Note : 127.0.0.1 = loopback

The IP address 127.0.0.1, also known as the loopback address, is reserved exclusively for localhost communication. This means it allows a computer to communicate with itself for testing and development purposes, rather than connecting to other computers.

In contrast, a private IP address such as 192.168.1.115 may be assigned to your computer by a router or local network so it can communicate with other devices within the same network.

In networking terms, the address 127.0.0.1 serves as an alias for the local machine. While regular IP addresses are used for connecting a computer to other systems or the internet, the loopback address functions as an internal connection within the same device.

For example, a web server installed on a computer might use 127.0.0.1 as the local hostname, allowing developers to run and test web pages locally before deploying them to a live server.

6. How an IP Address Works

When a device connects to a network:

  1. It is assigned an IP address (manually or automatically via DHCP).
  2. When it sends data, the IP address is included as:
    • Source Address (sender)
    • Destination Address (receiver)
  3. Routers use these addresses to deliver data packets correctly.

Example:
When you access www.google.com,

  • Your computer sends a request to Google’s IP (e.g., 142.250.190.14).
  • The web server sends the webpage data back to your computer’s IP.

7. Difference between IPv4 and IPv6

Feature IPv4 IPv6
Address Length 32-bit 128-bit
Format Decimal (e.g., 192.168.1.1) Hexadecimal (e.g., 2001:db8::1)
Total Addresses ~4.3 billion Virtually unlimited
Header Complexity Simple Complex but efficient
Security Optional (via IPSec) Mandatory (IPSec built-in)
Configuration Manual or DHCP Auto-configuration supported

8. Tools to Find IP Address

You can find your IP address using:

9. Real-Life Example

Let’s say you are visiting a school website:

  • You type: www.csaccept.com
  • Your computer sends a request to the DNS server.
  • The DNS server converts the domain name into an IP address, for example:
    192.185.129.70
  • Now your browser connects to that IP and loads the website.

So, www.csaccept.com → 192.185.129.70

10. Conclusion

An IP Address is the foundation of Internet communication.
It allows devices to identify each other, exchange data, and maintain connectivity across networks.
Without IP addresses, it would be impossible to locate or communicate with other devices on the Internet.

In Short:

IP Address = Unique Identity + Network Location of a device on the Internet.