Last updated Sep 8, 2023 at 8am ET
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IPs, or Internet Protocols, are addresses that computers use to communicate with the internet to fetch information. The original Internet Protocol introduced in the 80s, IPv4, is still widely used today. However, a newer iteration – IPv6 – was created to address certain issues concerning its predecessor.
Both IP types currently coexist, with a push to finally entirely switch to IPv6. But what does this entail to the average person just surfing the web? And what’s the difference between the two protocols, especially in terms of security and speed? Finally, how does it affect VPN users? We’ll cover all the pressing questions below.
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What is IPv4?
IPv4 (Internet Protocol version 4) identifies devices on a network by utilizing an addressing system. Each device accessing the internet is assigned a unique numerical IP address by using a 32-bit address scheme. It consists of 4 numbers, ranging from 0-255, separated by dots. An example of an IPv4 address is:
169.168.25.8
IPv4 has been in use since 1983 and as of today, it is the backbone of the internet, carrying around 95% of traffic. The problem is that it supports a maximum of ~4.3 billion unique IPs. It was deemed more than enough back in the day when a household used just a computer to surf the web. But now that we’re using smartphones, tablets, laptops, and all kinds of other devices for that, we’re quickly running out of IPv4 addresses.
With that in mind, it would be appropriate to suggest that IPv4 is coming to the end of its life and needs to be replaced sooner rather than later. And IPv6 seems like the perfect candidate to take the mantle. But is this newer iteration of the Internet Protocol the answer to these problems? Let’s take a closer look at this newer protocol.
What is IPv6?
IPv6 (Internet Protocol version 6) works in the same manner as IPv4, albeit it uses a 128-bit address format that also includes letters along numbers. Naturally, it’s much longer and allows the creation of a lot more unique IP addresses. We’re talking about 340 undecillion IPs instead of a measly 4.3 billion.
IPv6 addresses are made up of 8 groups of digits separated by colons. An example of such an address would be:
2008:0ce2:9d77:0000:0000:e4e0:0833:8008
Despite being introduced in 1995, IPv6 implementation has been exceedingly slow, so both protocols are being used simultaneously. The issue at hand is that there is no way to instantly jump from one IP type to another when almost everything still runs on IPv4.
Transition mechanisms are being rolled out, like Dual-stack IP, but it takes a lot of time and money to change older devices with new ones. If you have a newer router, it’s very likely that you already are connected to IPv4 and IPv6 at the same time. Internet Service Providers (ISPs) are also providing customers, both private and businesses, with public-facing IPv6 addresses.
IPv6 comes with plenty of benefits, such as:
- Autoconfiguration, which automatically generates an IPv6 address once a device accesses the internet for the first time
- Built-in data authentication, data encryption (IPsec), and other security measures
- Better speeds due to having a simpler header format
- Support for QoS (Quality of Service), namely Traffic Class and Flow Label, that help with routing traffic flow
- Multicasting, which reduces network bandwidth by sending bandwidth-intensive packet flows to multiple destinations simultaneously
- No more NAT, which leads to better speeds
However, IPv6 isn’t a flawless solution. It may cause compatibility issues with certain devices connected to the same network, DNS leaks when using a VPN, the creation of shadow networks, packet fragmentation, and so on. Some legacy systems and devices simply don’t support IPv6; the only solution is replacing it with entirely new ones, which is costly.
And we must note that while IPv4 and IPv6 can exist together on the same network, they can’t communicate with each other. That’s why it’s not fully implemented.
What are the main differences between IPv4 and IPv6?
Earlier in the guide, we took a closer look at each protocol individually. Here’s a table which showcases the differences between IPv4 and IPv6:
| IPv4 | IPv6 | |
| IP address | 32 bits | 128 bits |
| Classes | Class A, Class B, Class C, Class D, Class E | No |
| Checksum field | Yes | No |
| Packet size | 576 bytes, optional fragmentation | 1208, no fragmentation |
| Fragmentation | By senders and forwarding routers | By senders |
| SNMP | Yes | No |
| Unicast | Yes | Yes |
| Broadcast | Yes | No |
| Multicast | Yes | Yes |
| Anycast | No | Yes |
| Encryption (IPsec) and authentication | No | Yes |
| Autoconfiguration | No | Yes |
| Mapping | Uses ARP to map to MAC address | Uses NDP to map to MAC address |
| DNS records | Address (A) records, maps hostnames | Address (AAAA) records, maps hostnames |
| Mobile device compatibility | Not suitable | Suitable |
The relationship between IPv4, IPv6, and VPNs
Currently, there aren’t many VPNs that support IPv6, as the protocol hasn’t yet fully taken off due to costs and being time-consuming to implement. As such, IPv4 is still widely used among the majority of VPN providers. It is a problem for people who use IPv6, though, as it may lead to DNS leaks.
It would be appropriate for us to suggest readers to stick to VPNs which utilize IPv4. If your internet is running on this protocol that is. But as IPv6 is set to replace it, maybe in the near future even, it’s worth looking into services that support IPv6. Especially since this Internet Protocol iteration includes enhanced security measures.
A hugely popular VPN provider NordVPN implemented IPv6 support back in 2017, with leak protection included on all platforms. This is great news for those who have concerns over their privacy. A handful of other services choose to block IPV6 traffic altogether, such as Proton VPN, CyberGhost, and ExpressVPN. These are also great options for those who wish to remain anonymous online.
What else to look for in VPNs with IPv6 support?
Besides taking care of IPv6, a secure VPN should also include anti-leak measures for DNS requests and WebRTC. Most importantly, it must employ the gold standard of encryption – AES-256. Other aspects we recommend taking note of are:
- A no-logs policy. It assures the provider doesn’t collect and store your information. Prioritize those with policies verified by independent third parties.
- Jurisdiction. Being based outside the influence of the Fourteen Eyes alliance is preferable as it indicates the VPN won’t be pressured into spying on its users.
- Reputation. A service with a spotless track record is, naturally, a better choice than one mired in scandals or ownership concerns. Transparency is hard to come by but highly valued.
Of course, having a sizable server fleet, plenty of features, and broad device support shouldn’t be overlooked, either. These ensure you actually have a great VPN experience besides bulletproof security.
How to disable IPv6?
You can also disable IPv6 on your computer if you want to avoid any potential VPN disruptions. We’ll cover how to do it on Windows, macOS, and Linux operating systems.
How to disable IPv6 on Windows
- Click on the Windows logo and head to Settings > Network & Internet > Status
- Scroll down until you find Change adapter options and click on it
- Right-click on your network and select Properties
- In the new window, uncheck the Internet Protocol Version 6 (TCP/IPv6) box and press OK
- Do this with every other network available and restart your PC
How to disable IPv6 on macOS
- Click on the Apple logo and head to System preferences > Network
- Select the first network from the list and click on Advanced
- In the TCP/IP tab, set the Configure IPv6 option to Off
- Press OK to apply the changes. You’ll have to do this with every new network you connect to.
How to disable IPv6 on Linux
- Open the Terminal and enter the command: sudo nano /etc/sysctl.conf
- Scroll down to the bottom of the opened file and paste in the following:
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1
net.ipv6.conf.tun0.disable_ipv6 = 1 - Press Ctrl+O and Ctrl+X to save the changes
- Enter sudo sysctl -p to apply the changes. That’s it.
Final thoughts
For now, IPv4 and IPv6 continue to exist side by side. But, in time, it certainly won’t be surprising for IPv6 to become the new standard. After all, it allows for a far greater range of IP addresses – something that is crucial in an age where the demand for IP addresses is probably the highest that it has ever been.
You may also like to read:
What is IP spoofing
How to hide your IP address
What is a proxy
What is a VPN kill switch
How to check if my VPN is working
FAQ
Which is better: IPv4 or IPv6?
As the newer iteration, IPv6 is better than IPv4. It used a 128-bit scheme, storing a significantly bigger IP address number. Furthermore, this version has more features and built-in security measures than IPv4.
What is faster: IPv4 or IPv6?
IPV6 is faster than IPv4. However, due to allowing larger packet sizes, IPv6 can be slower in certain scenarios.
Why use IPv6 over IPv4?
We’re slowly switching from IPv4 to IPv6 as it can provide a much larger number of IP addresses. But it also comes with advanced features, traffic flow management for better speeds, and better security measures. In the long run, IPv4 will become obsolete and IPv6 will be the new standard.
Can we use both IPv4 and IPv6?
Yes, you can use IPv4 and IPv6 at the same time. Some devices support dual-stack addressing and can communicate with IPv4-only, IPv6-only, or other dual-stack devices. With the latter, the devices agree on which Internet Protocol version to use.
Gradually, IPv6 would replace the older version and I think everyone would have to adapt to the technology. It’s amazing how complex technology can be.
Indeed Ipv6 is an important factor for VPN users. This protocol is designed for the growth of the internet and it is achieved by ensuring that the total amount of data traffic transmitted and the number of connected hosts will be able to increase at a steady pace
That was really instructive ! I kind knew what both were but without really knowing what was different between them. Thanks a lot for the article now I get it 🙂
There is so much to keep track of with these things. It’s insane to think if you miss one little detail – like IPv4 or 6 – that you could be putting your data at risk. Frankly I’m a little exhausted by it all – how does anyone ever keep up? I never would have even known to check for that before now. Thanks for the heads up.
I know! it’s all so much and as much as I try to learn I just end up more paranoid that I’ve missed something else. There are so many tiny details to remember and so many people out there ready to exploit you for your data. I can get super depressed if I think about it too much for a second lol.
It’s quite interesting to think that back when the Internet was being invented, they didn’t know it was going to be as revolutionary as it is today. It was just a bunch of universities and government places. They designed IP addresses with the ability to have 4 billion unique addresses, thinking they would never need that many. How wrong they were.
IPv4 was the first stable version of Internet Protocol, and it still is widely used. IPv6 is the most recent version and is intended to replace IPv4, but I think there is still a long way to go before IPv4 is replaced by IPv6.