Time for some real talk.
Here's the hard truth, the IANA is out of IP addresses.
When IPv4 was first developed,
a 32-bit number was chosen to represent the address for a node on a network.
The Internet was in its infancy, and
no one really expected it to explode in popularity the way it has.
32 bits were chosen, but it's just not enough space for
the number of Internet-connected devices we have in the world.
IPv6 was developed exactly because of this issue.
By the mid 1990s, it was more and
more obvious that we were going to run out of IPv4 address space at some point.
So a new Internet protocol was developed, Internet Protocol version 6, or IPv6.
You might wonder what happened to version 5 or IPv5.
It's actually a fun bit of trivia.
IPv5 was an experimental protocol that introduced the concept of connections.
It never really saw wide adoption, and
connection state was handled better later on by the transport layer and TCP.
Even though IPv5 is mostly a relic of history, when development of IPv6 started,
the consensus was to not reuse the IPv5 name.
The biggest difference between IPv4 and
IPv6 is the number of bits reserved for an address.
While IPv4 addresses are 32 bits, meaning there can be around 4.2 billion individual
addresses, IPv6 addresses are 128 bits in size.
This size difference is staggering once you do the math.
Don't worry, [LAUGH] we won't make you.
2 to the power of 128 would produce a 39-digit-long number.
That number range has a name you've probably never even heard of,
an undecillion.
An undecillion isn't a number you hear a lot because it's ginormous.
There really aren't things that exist at that scale.
Some guesses on the total number of atoms that make up the entire planet Earth and
every single thing on it get into that number range.
That should tell you we're talking about a very, very large number.
If we can give every atom on Earth its own IP address,
we're probably be okay when it comes to network devices for a very long time.
Just for fun, let's look at what that number actually looks like.
It looks like this.