IP Address

An IP address (Internet Protocol address) is a unique identifier assigned to a device on a network, used to send and receive data over the internet or a local network.

Types of IP Addresses

1. IPv4 (Most common)

• Format: 192.168.0.1
• 4 sets of numbers (0–255)
• ~4.3 billion possible addresses

2. IPv6 (Newer, for scale)

• Format: 2001:0db8:85a3:0000:0000:8a2e:0370:7334
• 128-bit address space
• Virtually unlimited

Categories

A. Public IP

• Globally unique
• Assigned by ISPs
• Used to identify your device on the internet

B. Private IP

• Used within local networks (LAN)
• Not routable on the internet
• Common 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

C. Static vs Dynamic

Type	Assigned by	Usage
Static	Manually set or reserved	For servers, printers, etc.
Dynamic	Given by DHCP (e.g., your Wi-Fi router)	Most consumer devices

Networking Basics

• Devices use IPs to identify each other and exchange data.
• IP addresses work with ports (e.g., 192.168.1.5:80) to direct traffic to the correct application.

Example

Device	IP Address	Type
Home router	192.168.0.1	Private
Laptop	192.168.0.101	Private
ISP Gateway	203.0.113.42	Public