IPv4 vs. IPv6: what is the difference between these two protocols?

IPv4 vs. IPv6

For the Internet to function as such+, a series of protocols and standards are necessary that make it possible for computers and other devices to communicate with each other. The network of networks requires connecting machines that are very different from each other but share the same network protocols. For example, to identify each device on the Internet or on our local network, we have the IP, a numerical code. And we are currently experiencing a period of transition between different versions of this protocol:  IPv4 and IPv6.

In a network,  each device must be identifiable, differentiated from the rest in order to be able to send it data or for it to communicate with another device to send an email, send a WhatsApp message or play online. That identifier is the IP, an acronym for  Internet Protocol or  Internet Protocol. It is one of the first network protocols that made what is now the Internet possible. His parents were Vint Cerf and Bob Kahn and the first version was released in 1974.

Since 1982, the version of IP used on the Internet has been known as IPv4. IPv4  addresses are easily recognizable. Four groups of numbers that include one, two, or three numbers per group. But there are so many electronic devices, appliances, and machines that connect to the Internet that IPv4 addresses fall short. The solution? Its successor version, IPv6, offers many more addresses for the  Internet of the future. Or rather of the present, since it has been implemented for years.

How does IPv4 work?

We said that an IP address identifies each device that connects to the Internet. From a personal computer or a server to a mobile phone, a watch, a smart light bulb, a television, or a smart washing machine. Any device that accesses the network of networks requires an identifying IP. A local IP, which is the one that allows the devices to contact the Router and vice versa, and a public IP, which is the one that identifies the device on the Internet. Locally, in your own home, IP addresses are of the type And on the Internet, IP addresses can be something like

But of course, network protocols like IPv4 have their limitations. IPv4 uses 32-bit addresses. This makes it possible for nearly 4.295 million IP addresses to coexist. But when it was designed,  the IoT devices that swarm our homes today did not yet exist. Today it is common to have televisions, lamps, light bulbs, plugs, thermostats, speakers, voice assistants, refrigerators, washing machines, bracelets, watches, intercoms, video surveillance cameras… And I’m sure I’ll leave a few. Each of these devices connected to the Internet requires its own IP. And although the public IP is usually assigned with each new connection and is not always the same, the saturation remains the same. Come on, we need more IP addresses.

But far from chaos coming, those who make the Internet possible have already thought about this problem. And hence the creation of IPv6, which began as a draft at the end of 1998 and became an Internet standard in 2017. It is the successor to IPv4 and promises to have IP addresses for a long time.

What is IPv6?

We said that IPv4 generated 32-bit IP addresses. IPv6 makes it 128 bit. In practice, this means that instead of 4.295 million addresses, the Internet will have 340 sextillion addresses. If a million equals 10 to the power of 6, a sextillion is 10 to the power of 36. The key is that instead of four groups of three numbers, IPv6 addresses use numbers but also letters. Numbers from 0 to 9 and letters from A to F. And are organized in eight groups of four figures and/or letters.

Another difference that we see at first glance between IPv4 and IPv6 is that the alphanumeric groups are separated by colons instead of periods. In practice, while a public IPv4 might be, a public IPv6 might be 2001:0db8:85a3:0000:0000:8a2e:0370:7334. Example found on Wikipedia.

Thanks to IPv6 we will be able to connect more and more devices around the world to the Internet. Also, both network protocols can coexist, IPv4 and IPv6. But what you are probably wondering is, will I be able to access the Internet with the IPv6 protocol from my current computer or phone? What do I have to do to make the jump from IPv4 to IPv6?

A transition that takes its time

Before IPv6 saw the light, other technologies were already created that has served as a temporary patch to solve the problem of the depletion of IP addresses in the world. One of them is known as NAT, which stands for  Network Address Translation and which we translate as  Network Address Translation. Some Internet providers, before implementing the IPv6 protocol in their networks, use this solution, specifically the one known as CG-NAT.

Basically, CG-NAT consists of sharing the public IP  between several connected devices. Specifically, between several clients of an Internet provider. This has the advantage of temporarily avoiding running out of IP addresses. But it has its drawbacks, such as higher latency or that we cannot open ports.

Movistar does not use this technology. Instead, it has been working on implementing IPv6  on its networks for years. But it is a change that affects one of the network protocols, a pillar that makes the Internet possible. Hence, it is necessary to make the transition little by little. Worldwide, Internet giants such as  Google, Facebook, Akamai, Comcast, Cisco, and Internode have been implementing IPv6 in their networks for years. Especially in countries and regions that are depleting their assigned IP addresses the fastest. And basically in the field of companies and ISPs. For the home user, there is still time.

In Spain, this problem is far from coming. Hence, the implementation of IPv6 was not approved at the political level until April 2011. In percentage, in the world, the adoption of IPv6 is around 30%. In Spain, 3%. You can check it yourself with this quick test. All in all, this is not bad. As the linked test explains, “most Internet Service Providers are not yet ready to provide IPv6 Internet to residential customers ”.

As users, for now, we do not have to do anything. Operating systems, applications, and web browsers have been incorporating support for IPv6 in their most recent versions. By the time we need this support, it will be readily available. The responsibility, at this time, is on the side of Internet providers. They are the ones in charge of connecting us to the Internet, so they will have to be the ones to implement IPv6 in their networks, something that we will hear more and more about in the coming years.