First of all, let's understand what is IPv4 and IPv6.
IPv4 is the IP address we are familiar with now, for example: 192.168.12.20
IPv6 looks like this:
1301:0db8:86a3:08d3:1319:8a2e:0370:7367
IPv4 looks much simpler, doesn't it?
So we use IPv4 well? Why use IPv6?
The answer is: IPv4 addresses are no longer sufficient.
The number of IPv4 addresses is 2^32, that is, 4.2 billion (4,294,967,296) addresses, 4.2 billion is already a lot, our earth has only 7 billion people, is it not enough?
The answer is: really not enough. As early as 2011, the IPv4 addresses of the Internet Assigned Numbers Authority (referred to as: IANA) have been allocated. Many of the IP addresses we use now are temporary and shared by everyone.
So many servers on the Internet need IP addresses. Our computers, mobile phones, IPads, smart TVs, and refrigerators all need IP addresses.
In 2020, the number of global IoT terminals has reached 50 billion, so 4.2 billion IPv4 addresses are far from enough.
IPv4 was proposed in 1981. At that time, there was no Internet and there were not many computers in the world. Experts were able to design 4.2 billion IP addresses, which left a huge space and was very aggressive. But they never expected that the development of computers and the Internet would be so rapid that all IP addresses would be allocated in just 30 years.
Is the IPv6 address enough?
In order to prevent repeating the mistakes of IPv4, experts used enough imagination when designing IPv6 addresses. The number of IPv4 addresses is 2^32, which will be used up soon, right?
Then it should be enough for me to expand to 2^64, right?
No, it's not safe enough. What if human beings want to rush out of the earth and go to the universe in the future?
Then 2^128!
So how big is 2^128?
2^128 ≈ 10^38
Converted to decimal number is:
340,282,366,920,938,463,463,374,607,431,768,211,456
I have already counted 38 zeros after 3 for you, so how big is this number?
If the whole earth is made of sand, then there will be about 10^22 grains of sand. If each grain of sand is assigned an IPv6 address, then each grain of sand can be allocated 1 billion IPv6 addresses, which is a very huge The numbers are far beyond our imagination.
What is the current status of the use of IPv6 addresses in my country?
In November 2017, the General Office of the Central Committee of the Communist Party of China and the General Office of the State Council jointly issued the "Action Plan for Promoting the Large-scale Deployment of Internet Protocol Version 6 (IPv6)". The "Action Plan" requires that it takes 5 to 10 years to form a next-generation Internet independent technology system and industrial ecology, and build the world's largest IPv6 commercial application network. The wave of IPv6 has really come.
According to the data of the National IPv6 Development Monitoring Platform, as of October 2020, the number of active IPv6 users in my country is 437 million, accounting for 48.30% of active users. The number of active IPv6 connections reached 1.346 billion, and the proportion of active IPv6 connections nationwide reached 71.37%.
IPv6 has come to us unconsciously.