What is IPv6?
So we've already looked at IP version 4 addresses in other articles, but there's a problem.
When an IP version 4 first came out, the people that designed it sat back in their chairs and said "we've done it, we've created every IP address that anyone will ever need".
How many addresses did they create?
The answer is 4,294,967,296 addresses.
Which sounds like a lot right?
But at the time they couldn't have imagined the massive explosion of devices that would require an IP address.
If you think about every device you own, like a PC, laptop, smartphone, TV, etc. it quickly became apparent that we would soon run out of IP version 4 addresses.
The solution is to eventually move over to the new IP version 6.
IP version 6 provides us with 340 trillion, trillion, trillion IP addresses.
Aside from the number of addresses, IP version 6 also brings a lot of other improvements that makes it a lot more efficient and practical.
So let's dive into what an IP version 6 address looks like.
Let's first remind ourselves of what an IP version 4 address looks like.
It's 32 bits in length & remember bits refer to the binary digits of the address.
It contains four sections called octets which are separated by dots and in theory, each octet can contain any number between 0 and 255.
Now we're familiar with our good old friend IP version 4, let's bring in an IP version 6 address.
An IPv6 address may looks like this:
Now at first this address looks pretty scary, but don't worry, we're going to break it down step by step.
First let's do some comparisons.
We know our IP version 4 address is 32 bit long, but IPv6 address is 128 bits long.
This is where we get our massive IP address space from.
IP version 4 has four sections called octets.
IP version 6 has eight sections, but these are commonly called hextets.
IP version 4 uses dots to separate objects, but IP version 6 uses codons (:) to separate hextets.
Let's go into some more detail.
The first thing you probably noticed is there are letters in this IP address.
IP version 6 is hexadecimal, meaning each character can be between 0 and 9 or A & F.
Let's take a look at how IP version 6 works when it comes to binary.
This is especially important when it comes to some subnetting.
Each hexadecimal character is made up of four binary bits.
These bits can either be a 0 or a 1.
Each bit represents a value of 1, 2, 4 or 8.
The value doubles with each column from right to left.
Wherever we see at 1 that toggles the column on and wherever we see a zero that toggles the column off.
We then add up all our columns that have a 1 and this gives us our number or letter.
So let's take the first number from the address, which is 2.
How do you think we can make the number 2 from our binary bits?
We simply add a one in the column that represents the value of 2.
All of the other columns stay zero, because we don't need them.
So the binary value for our first number is 0 0 1 0.