An IP address (Internet Protocol address) is a unique numerical identifier assigned to a device in a computer network that uses the Internet Protocol for communication. It functions like a postal address in the physical world, indicating where data packets should be sent and from where they originated.
IP addresses are used in all TCP/IP-based networks, including private LANs and the global Internet. Every device connected to a network—such as servers, computers, routers, smartphones, or IoT devices—receives an IP address, either permanent (static) or temporary (dynamic).
IP Address Formats
- IPv4 (Internet Protocol version 4): The most widely used format, consisting of four decimal numbers (octets) separated by dots, such as 192.168.0.1. IPv4 provides approximately 4.3 billion unique addresses.
- IPv6 (Internet Protocol version 6): A newer format using 128-bit addressing, written in hexadecimal and separated by colons, such as 2001:0db8:85a3:0000:0000:8a2e:0370:7334. IPv6 was developed to solve the address exhaustion issue of IPv4.
Types of IP Addresses
- Public (External): Used for Internet access and visible outside your local network.
- Private (Internal): Used within local networks (e.g., 192.168.x.x, 10.x.x.x) and not routable on the public Internet.
- Static: Manually assigned and remains constant over time.
- Dynamic: Automatically assigned, typically via DHCP, and may change with each connection.
Why IP Addresses Are Important
- To route traffic between devices
- To establish connections (e.g., to websites or servers)
- To identify users or devices on a network
- For access control, traffic filtering, geolocation, and activity logging
The Role of IP Addresses in Telecommunications
For service providers, IP addresses are a fundamental component of network connectivity. ISPs allocate IP addresses from their pools or route them via protocols like BGP. In business environments, dedicated (public) IP addresses are often required for hosting servers, VPNs, email infrastructure, and secure remote access.