What is an IP Address?

If you’ve checked out the add-ons hawked by most hosting providers these days, you’ve probably seen the term “dedicated IP address” floating about. You’ve also probably wondered why you should pay for one. With this series of articles, Comparakeet helps you answer that question–along with other questions you might have about IP addresses in general.

This week, we kick things off with the fundamental question: What is an IP address, anyway?

IP stands for “Internet Protocol,” and that should give you a hint about what it’s for. Simply put, an IP address identifies hardware devices on a network. Each device gets a unique sequence, which other devices use to find and communicate with it. Think of it like a license plate, or even a fingerprint.

Bear in mind, too, that “device” isn’t limited to computers. Any kind of device, from your smartphone to your wireless printer, gets a unique IP address when it connects to a network.

Reading IP Addresses

You might have seen the terms “IPv4” and “IPv6” floating around. Those are just names for the two standards currently used for IP addresses.

When these addresses started being used, IPv4 was the only system, and it’s universally supported to this day. IPv4 addresses use four sets of numbers, each ranging from 0 to 255. They look like this:

  • 168.1.1
  • 0.255.255

All told, IPv4 addresses allow for 232 different addresses–more than 4 billion. But consider how many people on the planet connect to the Internet using an arsenal of devices. Even with that vast number, IPv4 just doesn’t allow for enough addresses to go around.

Enter IPv6, the newer version that’s gradually supplanting IPv4 throughout the Internet. Where IPv4 addresses were 4 bytes or 32 bits long, IPv6 goes much further with 16 bytes or 128 bits. What does that mean for the regular ol’ network? It means there can now be 2128 IP addresses–340,000,000,000,000 in all. IPv6 is the Oprah of IP address systems–you get an IP address, they get an IP address, everybody gets an IP address.

To accommodate the drastically larger number of possible addresses, IPv6 uses hexadecimal digits instead. That means addresses now look like this:

  • 3ffe:1900:4545:3:200:f8ff:fe21:67cf
  • 2001:0db8:85a3:0000:0000:8a2e:0370:7334

Types of IP Addresses

Each IP address is either IPv4 or IPv6, but there’s also a whole host of address types according to how the address is used. IP addresses can be static or dynamic, public or private. We’ll explore those distinctions more in future articles, but here’s a quick overview.

Static vs Dynamic

Static addresses are exactly what the name says: these are addresses that don’t change. That’s important because there are systems where a device gets randomly assigned a new IP address whenever it connects to a network or after a certain interval of time has passed. In those cases, that device gets what’s called a dynamic IP address instead. All IP addresses are either static or dynamic.

Private vs Public

Private IP addresses, meanwhile, identify devices within a smaller network. Think of it this way: within the large circle defined by the worldwide web, there’s a smaller circle defined by your router and all the devices connected to the specific network it projects. Private IP addresses allow your laptop to find your wireless printer or know which wireless speaker set to stream music with. These IP addresses are assigned by your router or given manually, depending on how your particular network is configured.

Public IP addresses, on the other hand, are used for the wider network that connects devices all over the world–in short, the Internet. These are assigned by your Internet Service Provider (ISP), and are what makes it possible for you to surf the web. For example: your computer uses IP addresses to identify and tap the server that houses a particular website.

What’s Your IP?

Identifying IP addresses is one of the trademark skills of movie hackers, so you might be surprised to learn that it’s not that hard to do for your devices. If you want to know what your IP address is, here’s what you do.

Public IP Address

There are lots of sites out there that will let you look up your public IP address. Check out WhatsMyIP.org, WhatIsMyIPAddress.com, and more. These are accessible from any browser, so you can use whatever web-enabled device you’ve got on hand.

Private IP Address

This is a bit trickier, and it depends on what device or system you’re using. For computers equipped with Windows or Mac OS, typing the ipconfig command into the command prompt or terminal will give you the information. For Linux, meanwhile, you can pick from hostname -I, ip addr show, or ipconfig.

Mobile devices will often have this information available somewhere in your device settings or system information page. Apple and Android devices, for example, will often have network information under the Wi-Fi or Wireless sections of their Settings.