Compared with IPv4, IPv6 is more than just an increase in address length

As we all know, the length of IPv6 IP address is four times that of IPv4 IP address, and it is a technology to solve the exhaustion of IPv4 public URL resources. Indeed, IETF also considered this factor when formulating the IPv6 standard. It was the early 1990s, when the Web began to appear, which led to the explosive development of IP networks, the rapid increase of IP network users, and the shortage of IP addresses. The problem that IPv6 had to solve was to expand the address space. Later, IETF gradually revised the IPv6 standard, and there were hundreds of RFC drafts. There were nearly 100 RFCs that formed the IPv6 standard. These RFC standards greatly enriched the connotation of IPv6 technology and gave IPv6 more meaning, not just the increase in the number of IP addresses. Next, we will reveal the benefits that IPv6 can bring to the network from the perspective of application.

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IPv6 IP addresses consist of 128 bits, and theoretically 7*10^23 IP addresses can be allocated, which is a very large number, enough to allocate an IP address to every grain of sand in the world. With so many IP addresses, there is no need to worry about the problem of insufficient IP addresses. As long as the device can access the Internet, it can be allocated several IPv6 addresses. The IPv6 addresses used for mutual access between devices are unique in the world, so IPv6 devices can be accessed no matter where they are. IPv4 is not the same, because the public network addresses are limited, everyone has to use private network IP addresses, and NAT conversion must be performed before accessing the Internet. On the public Internet, it is impossible to ensure that all addresses can directly access each other.

IPv6 not only solves the problem of insufficient IPv4 addresses, but more importantly, it can solve the obstacles for various access devices to connect to the Internet. A large number of computers, mobile phones, smart home appliances, and wearable devices can be connected to the Internet and access each other, which lays the network foundation for the development of the Internet of Things. Why is the country so urgent to force the promotion of IPv6? It is to pave the way for the Internet of Things. Otherwise, although the existing IPv4 addresses are not enough, they can still be used through various technologies. However, for the Internet of Things, to realize the interconnection of all things, no IPv4 technology can meet the needs, and only IPv6 can achieve it. Therefore, it is the IPv6 technology that has opened the curtain for the development of the Internet of Things.

Since there are so many IPv6 addresses, each Internet device can be assigned a unique IP address in the world, and such IP addresses can be effectively traced. IPv6 addresses are like telephone numbers. The first few digits of the number will tell you where the user registered from, and your identity information will be displayed. Because each address is truly unique, it is equivalent to assigning a "network identity" to each person technically. Each person or each device has such an identity certificate, through which it can quickly find its location, as well as its surrounding environment information and network characteristics, to achieve precise positioning. IPv6 also has a verification system for source addresses, which can better meet the identity authentication and network risk resistance required by financial-level applications, and IPv6 has a qualitative improvement in security.

IPv6 not only has a longer IP address, but also a longer IP header. IPv6 no longer uses the fixed 20-byte message header of IPv4 address, but can add some optional headers to IPv6. These optional headers can be carried or not carried by IPv6, which depends entirely on the application needs. Of course, some security headers can also be carried to encrypt the data and improve the security of message forwarding. Based on IPv6 technology, we can do more security things, which is much more flexible than the IPv4 era. So many network leaks have occurred and are still vivid in our minds. IPv6 technology may really change this situation, especially for individual users. Now IPv4 IP addresses are shared. Many people share a public IP address and Internet traffic is also shared. IPv6 can be exclusive, and it is truly exclusive in terms of network traffic.

5G is really coming. This is another major change in the mobile communication network, and IPv6 is also the basic protocol for the development of 5G. 5G is a gradual development from mobile calls to mobile communications. It mainly solves the problem of local wireless connection. Devices that connect to the Internet through 5G need IPv6 to define their IP addresses. 5G is the alleys and small streets, and IPv6 is the main road. The development of 5G cannot be separated from IPv6. In fact, if we turn on our mobile phones and check carefully, many 4G mobile phones used for mobile Internet access use IPv6 addresses. The three major operators have already opened 4G networks that support IPv6 at multiple addresses. From the perspective of mobile phone users, there is no difference between using IPv6 and IPv4 addresses. In fact, from a technical point of view, IPv6 has better mobility. RFC3775 specifically explains the mobility of IPv6, which is not available in IPv4.

IPv6 mobility technology is a new routing strategy introduced on the basis of the original IPv4 technology. The upper layer services based on IP addresses will not be interrupted due to the movement of nodes. This mobility is based on the third layer, thus shielding the heterogeneity of the underlying links. When the mobile node leaves the home link and connects to some foreign links, the IPv6 mobility function begins to play a role. After connecting to the foreign link, the mobile node obtains an IPv6 address on the foreign link, which is called a care-of address. The mobile node sends a binding request to its home agent with the new address. The home agent binds the home address of the mobile node to the care-of address and establishes a tunnel between the two. The upper layer data communication cannot feel this change. In other words, the IPv6-based application will not be terminated due to the movement of the device. This is the characteristic of IPv6 mobility technology.

Of course, there is one more point that must be mentioned. When faced with the rapid increase in the number of mobile terminals, only IPv6 can assign a global IP address to each device. Mobile IPv6 is easy to expand and has the ability to handle large-scale mobility requirements, so IPv6 will be able to solve the mobility problem between global networks and various access technologies.

The benefits of IPv6 at the application level are more than these. For example, IPv6 simplifies the format of the message header, with only 8 fields, speeding up message forwarding and increasing throughput, which is equivalent to reducing network latency from the current 100MS to single digits; the rate of cybercrime has been greatly reduced, and IPv6 can trace the source. If anyone does something bad online, the source can be found immediately; IPv6 has optional headers, allowing the protocol to continue to evolve and add new functions, making IPv6 have many possibilities, and... There are really many benefits in this list, but people usually don't notice them. Technology is constantly accumulating and progressing. IPv6 technology is naturally designed on the basis of IPv4 technology, taking the essence and discarding the dross. It is inevitable that it has many advantages over IPv4 technology. Now, the whole country is promoting the implementation of IPv6 networks, and large-scale commercial use is required to complete the process of IPv6 from theory to practice. IPv4 network technology has been developed for decades, and the technical concept has been deeply rooted in people's hearts. It will be a long process to completely switch to IPv6 network technology. Let us look forward to it.