What is IP Address?
IP Address (Internet Protocol Address) is a unique numerical identifier assigned to every device connected to a computer network that uses the Internet Protocol for communication. It serves two main functions: host identification and location addressing.
Quick Facts
| Full Name | Internet Protocol Address |
|---|---|
| Created | 1981 (IPv4), 1998 (IPv6) |
| Specification | Official Specification |
How IP Address Works
IP addresses come in two versions: IPv4 and IPv6. IPv4 addresses are 32-bit numbers typically written as four decimal numbers separated by dots (e.g., 192.168.1.1), providing about 4.3 billion unique addresses. Due to address exhaustion, IPv6 was developed with 128-bit addresses written in hexadecimal (e.g., 2001:0db8:85a3::8a2e:0370:7334), providing virtually unlimited addresses. IP addresses can be public (routable on the internet) or private (used within local networks). DHCP typically assigns addresses dynamically, while servers often use static addresses.
Key Characteristics
- IPv4: 32-bit, ~4.3 billion addresses (e.g., 192.168.1.1)
- IPv6: 128-bit, virtually unlimited addresses
- Can be public (internet) or private (local network)
- Dynamic (DHCP) or static assignment
- Includes network and host portions
- Subnet masks define network boundaries
Common Use Cases
- Device identification on networks
- Routing internet traffic
- Geolocation and content delivery
- Network security and access control
- Server hosting and DNS resolution
Example
IPv4 Address Examples:
192.168.1.1 - Private (home router)
10.0.0.1 - Private (corporate)
172.16.0.1 - Private
8.8.8.8 - Public (Google DNS)
IPv6 Address Examples:
::1 - Localhost
2001:4860:4860::8888 - Google DNS
fe80::1 - Link-local
Private IP Ranges (IPv4):
10.0.0.0 - 10.255.255.255 (Class A)
172.16.0.0 - 172.31.255.255 (Class B)
192.168.0.0 - 192.168.255.255 (Class C)
Subnet Notation:
192.168.1.0/24 = 256 addresses
10.0.0.0/8 = 16.7 million addresses