IPv4 addresses are finite
Internet protocol version 4 is the most popular protocol as of now. An IPv4 address record consists of four numbers from 0 to 255, separated by dots.
This format assumes 4.3 billion combinations. This is not much in the digital age: as the number of devices is growing every day, IPv4 addresses are running out. The problem became especially acute with the advent of the Internet of Things. Now even car alarms, TVs, smart fridges, and medical devices have access to the Internet and thus, need an IP address.
How restrictions are handled
There were multiple attempts to solve the problem of the IPv4 address shortage.
One of them was to use dynamic IP addresses, which were assigned to the device only when it was connected to the network. Once the device was disconnected, its IP address was given to another device. Now smartphones demand an almost constant network connection, and many services require a permanent static IP address. Dynamic IPs are therefore no longer covering the needs of users.
The most common solution now is using private IP addresses. Instead of leasing a globally routable IP address to each device, a special device called router gives them addresses valid only within a local network. The router has a role of a gateway between the devices and the Internet. The whole traffic to the outside world goes through it and the clients within the local network share a single public IP address to access the Web.
IPv6 addresses won’t run out
The introduction of a new Internet protocol has improved the situation. Four times the length of IPv4 addresses, an IPv6 address consists of eight groups of four characters from 0 to 9 and Latin letters from a to e, separated by colons. Here’s an example of an IPv6 address:
It is assumed that people can never run out of IPv6 addresses. With the introduction of IPv6 addresses, it is now possible to assign a unique address to every device in a house.
Why isn’t IPv6 widely used yet?
Although IPv6 seems to solve the IPv4 address scarcity problem, not all websites and providers support it — and there are reasons why.
IPv4 and IPv6 addresses are not backward compatible: you cannot access IPv4 websites with IPv6, and vice versa.
Not all ISPs support IPv6 yet, but they all support IPv4.
Not all websites support IPv6.
IPv6 is a technology that requires considerable technical skill and investment of time. In addition to configuring the protocol, you also have to reconfigure the firewall and devices on the network.