What is IP Address Glossary?

Plain-language definitions for common networking terms: IPv4, IPv6, DNS, DHCP, NAT, VPN, MAC address, firewall, subnet, and more.

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IP Address Glossary

Key networking and IP terms explained in plain language.

DHCP

Dynamic Host Configuration Protocol. The system that automatically assigns IP addresses to devices on a network. Your router uses DHCP to give each device its private IP address.

DNS

Domain Name System. Translates human-readable domain names (like bestipaddress.com) into IP addresses (like 104.21.45.67) that computers use to find each other.

Dynamic IP

An IP address that can change over time, assigned temporarily by your ISP via DHCP. Most home internet connections use dynamic IPs. Learn more →

Firewall

A security system that monitors and controls incoming and outgoing network traffic based on predetermined rules. Firewalls use IP addresses to allow or block connections.

Gateway

The device (usually your router) that connects your local network to the internet. It acts as the entry/exit point for all traffic between your devices and the wider internet.

Geolocation

The process of estimating a device's geographic location based on its IP address. Accuracy varies from city-level to region-level. Learn about accuracy →

IPv4

Internet Protocol version 4. Uses 32-bit addresses formatted as four numbers separated by dots (e.g., 192.168.1.1). Supports approximately 4.3 billion unique addresses. Learn more →

IPv6

Internet Protocol version 6. Uses 128-bit addresses formatted as eight groups of hexadecimal digits separated by colons (e.g., 2001:db8::1). Provides virtually unlimited addresses. Learn more →

ISP

Internet Service Provider. The company that provides your internet connection (e.g., Comcast, AT&T, Spectrum). Your ISP assigns your public IP address.

LAN

Local Area Network. A network connecting devices in a limited area, like your home or office. Devices on a LAN communicate using private IP addresses.

MAC Address

Media Access Control address. A unique hardware identifier assigned to every network interface card. Unlike IP addresses, MAC addresses are permanently assigned to the physical device and don't change.

NAT

Network Address Translation. The process your router uses to translate between private IP addresses (used by your devices) and your single public IP address (used on the internet). Learn about public vs private IP →

Proxy

A server that acts as an intermediary between your device and the internet. Similar to a VPN in that it can mask your IP, but typically without encryption.

Static IP

An IP address that never changes, permanently assigned to your connection by your ISP. Usually costs extra and is used for servers and remote access. Learn more →

Subnet

A subdivision of an IP network. Subnets help organize devices and manage traffic within larger networks. A common home subnet is 255.255.255.0.

VPN

Virtual Private Network. Creates an encrypted tunnel that hides your real IP address and protects your internet traffic from monitoring. Full VPN guide →

WAN

Wide Area Network. A network that spans a large geographic area, like the internet itself. Your public IP is your address on the WAN.

Understanding Your IP Address

Your IP (Internet Protocol) address is a unique numerical label, which has direct implications for anyone researching glossary topics. See the sections above for specifics.

Public vs private IP: Public vs private IP: Your public IP address, and for glossary the practical impact is visible in the data above. See the sections above for specifics.

What your IP reveals: What your IP reveals: Your public IP address, and this holds true whether looking at glossary or similar topics. See the sections above for specifics.

IPv4 vs IPv6: IPv4 vs IPv6: The older IPv4 standard uses, which the glossary case study on this page illustrates well. See the sections above for specifics.

Protecting your privacy: Protecting your privacy: If you want to mask, which the glossary case study on this page illustrates well. See the sections above for specifics.