The main difference between IPv4 and the newer IPv6 is the availability of addresses. IPv6 offers over 1,000 times the number of unique addresses offered by IPv4. There are some other technical differences that make IPv6 more secure and flexible, but its speed is usually the same as IPv4.
An internet protocol (IP) is a set of rules used to move packets of information through the internet to their intended destination. There are currently two IP versions in use: IPv4 and IPv6. We’ll start with how IP addresses work, then get into what IPv4 and IPv6 are.
IP Addresses: A Quick Rundown
When information is sent via the web, it gets broken down into pieces called data packets. In order to make sure the data gets reassembled in the right place, internet-connected devices have IP addresses that tell data where to go.
Every smartphone and desktop computer, for example, has an IP address, but devices like printers and smart speakers also have them because they’re connected to the internet and receive data. Data gets routed to a specific IP address by the network, helping it find your device among all the others connected to the internet.
What Is IPv4?
IPv4 is the first version of the internet protocol to be widely used. It stands for, unsurprisingly, Internet Protocol Version 4. It was first released in 1983 and is still in use today.
IP addresses using this protocol are groups of 11 digits separated by periods, called dotted hexadecimal notation. An example of an IPv4 address would be:
192.168.10.150
Each number in an IP address stores information that tells data packets where to go. Each group of numbers can store one byte of information, and there are four groups in each IPv4 address, which adds up to 32 bits total of information storage. For that reason, the IPv4 addressing system is known as a 32-bit system.
This system allows for up to 4.3 billion unique addresses, which sounds like a lot until you realize just how many people and devices are connected to the internet today. Devices in the Internet of Things (IoT) also need IP addresses. That explosion of use as our lives become increasingly internet-connected means the IPv4 addressing system is running out of space. Enter IPv6.
What Is IPv6?
IPv6 is a newer version of the internet protocol with longer addresses containing both numbers and letters. Though newer than version 4, it’s not that new: it was first deployed in 1999.
IPv6 addresses have 128 bits of information storage. They’re written in hexadecimal colon notation, meaning each group of numbers and letters is separated from the next by a colon (:) instead of a period.
An example IPv6 address would look like this:
3002:0bd6:0000:0000:0000:ee00:0033:6778
This longer addressing system supports 2^128 unique addresses, or 1,028 times the number of IPv4. 4.3 billion multiplied by 1,028 is… enough unique IP addresses that we won’t have to worry about running out of them anytime soon.
IPV4 vs. IPV6: How Are They Different?
The main differences between the two are the length of each IP address and the overall number of unique addresses available, but there are additional, more technical variations between the two versions.
Some of the main features of IPv4 include:
- Connectionless Protocol
- Allows creation of a simple virtual communication layer over multiple devices
- Requires less memory
- Increased ease of remembering addresses
- Already supported on millions of devices
Main features of IPv6 include:
- No NAT (Network Address Translation) allowing end-to-end connectivity at the IP layer
- Multi-casting (transmission of a data packet to multiple destinations at once) is included standard
- Prevents private address collisions
- Simpler header format
- Simplified, more efficient routing overall
- True quality of service (QoS), or “flow labeling”
- Built-in security layer (IPsec)
- Flexible options and extensions
- Easier administration (no more DHCP)
IPv6 is more secure, more flexible, and allows for a much greater number of unique addresses than IPv4. IPv4 and IPv6 are also written in different formats, with IPv4 made up of numbers separated by periods and IPv6 addresses made up of numbers and letters, separated by colons.
Frequently Asked Questions
Is IPv4 faster than IPv6?
Most of the time, IPv6 doesn’t appear to be much faster than IPv4. Cloud-based tech company Sucuri tested the two IPs against one another in multiple scenarios and didn’t appear to find much of a difference in speed.
There are some situations where IPv6 seems to be faster, though. Facebook ran a test back in 2015, for example, and determined its website loaded 10-12% faster on IPv6. The large number of variables between the two makes it difficult to see which is faster without extensive testing in a highly controlled environment.
How much of the world uses IPv6?
Since it’s been around longer, IPv4 is more widely used, but IPv6 adoption is growing as addresses on the older IP run out. According to Google data, around 40% of the world has adopted IPv6 as of June 2023. Google also breaks down that data by country, which varies pretty widely. The U.S., for example, is at over 50% adoption while Australia is at just over 29%, Sweden is at 19%, and Argentina is at 18.4%.
If you want to learn more, check out whether you should be using IPv6 on your home computer, or whether your server needs IPv6 connectivity.
