What is the difference between IPv4 and IPv6?

There is enough information on IPv4 and IPv6 to fill an entire e-book – so we’re going to try and cover a very basic understanding of what IP is and how IPv4 and IPv6 fit into the grand scheme of things. If you have any additional specific questions, just leave a comment below and we’ll be happy to answer it!

What is Internet Protocol (IP)?

Internet Protocol is a communication standard, established to allow devices around the world to communicate with each other. It’s a relatively universal system, used to send pieces of data back and forth between two points on a network. It’s connectionless, in that you don’t need to have a direct physical connection between two machines in order for them to communicate. As long as each one knows the other’s address, the data can be transmitted along the network.  Much like our roadway system: You don’t need a direct road from your house to your friend’s house, as long as you know the final address you can figure out how to get there along the way.

What is an IP Address?

You’re probably more familiar with the term IP Address, which is a set of numbers used to identify a particular machine on the internet.
The Internet Protocol is very similar to our FedEx/UPS/USPS Mailing systems. Your computer takes a piece of information, puts an IP address on it, and hands it off to its Router – which then ships it along the internet to its final destination. While there are some more complicated steps along the way, this is pretty much the basics of it.
Just like our mailing systems: You put a home address (IP Address) on a letter (piece of data) and drop it off at the Post Office (your router).

What is IPv4?

IPv4 stands for Internet Protocol version 4, and is the predominate version of IP used in routing packets of data across networks.

IPv4 uses a 32-bit addressing system that looks like this:
This format is probably one that we’re very familiar with in the IP world.

In essence, each machine connected to the internet or a network has an address that looks very similar to that. That unique address is what allows points along a network to identify and carry data back and forth.
Due to this addressing convention, there actually is a maximum number of IP addresses available in the entire world: 4,294,967,296 IP Addresses to be exact.

In February of 2011 – we actually ran out of available numbers. This “IP Exhaustion” was anticipated, and in the 1990s the IPv6 was developed and finally adapted around 2006.

What is IPv6?

IPv6 is similar in its purpose to IPv4, but uses a different numbering scheme in order to accommodate for many more IP Addresses.

340 Undecillion

That’s the number of addresses that are available using IPv6. No, I’ve never heard of that number either – but it’s apparently the number 340 with 36 zeroes after it. It looks like this…


Is That The Only Difference?

There are a lot of technical differences between how hardware handles the two different internet protocols – but the end result is pretty much the same. For the scope of this post, we only really need to know that the difference is in the amount of addresses available.
A lot of new hardware is compatible with both IPv4 and IPv6, and I don’t think that IPv4 will ever cease to completely exist – but as new computers come on to the Internet, they’re going to have to start using IPv6, so there is an important function in knowing whether your company’s hardware is compatible with this. Check with the manufacturers of your Routers, Switches, Firewalls, SBCs and Computers to make sure that they can handle both IPv4 and IPv6.