Exploring IPv6: Back to the Basics. What Is an IP Address?

Exploring IPv6: Back to the Basics. What Is an IP Address?

On the second Friday of every month for the next six months, we plan to embark on an exploration of what lies beneath the surface of the Internet. Today, we will start off by looking at the mysterious Internet Protocol (IP) address:what is it exactly, and how many different types of IP addresses are there?

An IP address is a number that uniquely identifies a device on a computer network and, using transport protocols, moves information on the Internet. Every device with an Internet connection, from cell phones and computers, to toasters and cars, must have a unique IP address, which enables communication between these devices.

There are two well-known standard types of IP addresses that are used today:

IPv4 (Internet Protocol version 4) is the first widely used standard defining how the Internet and its connected devices operate and communicate with one another. With 4.3 billion IP addresses, it is simply no longer enough to support the growth of the global commercial Internet. The world is running out of IPv4 addresses, which means Internet stakeholders need to adopt a new kind of IP address.

IPv6 (Internet Protocol version 6) is a more robust numbering system than IPv4 that allows for far more IP addresses. About 340,282,366,920,938,463,463,374,607,431,768,211,456 IP addresses to be exact. Many organizations around the world are now deploying IPv6 in an effort to keep up with the growth of the Internet. For an in-depth look at the technical aspects of IPv6, take a look at this presentation.

But wait, IPv4 to IPv6? What ever happened to IPv5? There never was an official IPv5 protocol. In the late 1970’s, a protocol named ST (The Internet Stream Protocol) was created for the experimental transmission of voice, video, and distributed simulation. It was abandoned before it could become an official standard. IPv6 however, was developed by the IETF and deployed in 1999 as the official standard protocol to meet the needs of a rapidly growing Internet. At the time it was also known as IP Next Generation or IPng. Today, we just call it IPv6.

If you want to investigate a little deeper into IP addresses, feel free to check out ARIN’s knowledge page, a one-stop shop for all your Internet number resources needs. Additionally, for some more in depth coverage of IPv6, be sure to visit the ARIN IPv6 wiki

Now that you know the different types of IP addresses, we bet you’re wondering where all of the IPv4 addresses have gone, don’t forget to tune in next month to learn more!

Post written by:

Jennifer Bly
External Relations Manager

Recent articles categorized under: IPv6

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