An IP Address is an identification number for a device on the Internet Protocol (IP) network. It identifies devices such as computers, tablets and smartphones, and enables them to connect with each other. It also allows them to communicate with destination services such as websites and streaming apps. IP addresses are a key part of how the internet works, and understanding them is important to anyone who uses it.
An important thing to remember about IP addresses is that they are not random. They are mathematically generated and assigned to devices by the Internet Assigned Numbers Authority, a division of the non-profit organization called the Internet Corporation for Assigned Names and Numbers (ICANN). There are two primary versions of IP addresses in use today: IP version 4 (IPv4) and IP version 6 (IPv6).
There are other versions of IP in the pipeline, but they aren’t yet ready for wide use. As of this writing, the vast majority of the world’s web servers and other devices use IPv4.
How Does an IP Address Work?
An IP address is a unique identifier that is assigned to every network-connected device on the world wide web. It acts like a postal address, letting the internet know where to send information for that device and how to get back to it.
A device typically has two IP addresses 192.168.l.0.1, one public/external and the other private/internal. The external IP address is the one that enables your device to connect to the wider internet, and the internal IP address is what lets your device talk to other devices in your home network such as your computer, smart TV or network-attached storage box.
The process for assigning an IP address to a device begins with ICANN, which maintains a registry of all registered domain names on the internet. When someone wants to register a website or other online service, they go through a domain name registrar, which pays a fee to ICANN to reserve that domain’s IP address.
As internet traffic grows, so does the need to provide more and more IP addresses to devices connecting to it. In 1999, experts worried that the Internet Assigned Numbers Authority (IANA) would run out of IPv4 addresses, so they designed a successor: IPv6. IPv6 has a pool of 340 undecillion addresses (that’s 340 followed by 36 zeroes), which should last far longer than the lifespan of current internet technologies.
There are many ways to find someone’s IP address, including using an online tool, checking the full header of an email or running various command prompts on a PC. However, it’s important to remember that any of these methods could be used by a malicious actor for nefarious purposes. For this reason, it’s important to remain discerning about who you communicate with on the internet.