Explanation of 128-bit IPv6 Protocol address

In the emergency of IPv4 network IP address exhaustion, we have become more urgent to use the IPv6 protocol. So how does IPv6 add IP addresses? Let's use the article to answer this question. First, let's take a look at the specific number of IPv6 protocol addresses.

Why is the IPv6 Protocol address 128 characters in length?

Some may ask, if the IPv4 address is not enough, I can add a few more addresses to IPv4. Why not add the IPv6 address to the first 128 bits?

This type of question is caused by a lack of understanding of the chip design and CPU processing methods, and insufficient foresight for future network expansion. In the chip design, we know that all values are represented by "0" and "1, the CPU processing wordlength has now gone through 4-bit, 8-bit, 16-bit, 32-bit, 64-bit, etc. We know that in the computer, when the data can be expressed by the binary number of 2 exponential power characters, the CPU has the highest processing efficiency. The IPv4 address corresponds to a 32-bit font because the CPU size of the host on the Internet was 32 bits.

Currently, 64-bit machines are widely used, and 128-bit machines are growing. Setting the address as 64-bit is insufficient in terms of network scalability. Setting the address as another length will reduce the efficiency of hardware chip design and programming, therefore, considering the processing efficiency and future network scalability, it is very appropriate to set the IPv6 address length to 128 bits.

What is the concept of a 128-bit IPv6 Protocol address?

IPv6 provides a 128-bit address space. The huge address capacity that IPv6 can provide can be described in the following aspects:

There are a total of 2128 different IPv6 addresses, that is, the number of globally allocable addresses is 340,282,366,920,938,463,463,374,607,431,768,211,456. If you are allocated by land area, you can get 2.2*1020 addresses per square centimeter.

The chances of IPv6 address depletion are very small. For a long foreseeable period, IPv6's 128-bit address length forms a huge address space that can provide a globally unique address for all conceivable network devices, IPv6's ample address space will greatly meet the address growth needs with the emergence of smart network devices, such as personal data Assistant PDA), Mobile Phone) and the home network access device HAN.

What is the IPv6 Protocol address?

IPv4 addresses are represented in dotted-decimal format. 32-bit addresses are divided into four eight-bit groups. Each eight-bit address is written in decimal format and separated by dots. The IPv6 128-bit address is a 16-bit grouping. Each 16-bit grouping is written into four hexadecimal numbers separated by colons, which are called the colon hexadecimal format. For example, 21DA: 00D3: 0000: 2F3B: 02AA: 00FF: FE28: 9C5A is a complete IPv6 address.

IPv6 addresses indicate the following special situations:

The leading zero position in each 16-bit group of an IPv6 address can be removed for simplified representation, but each group must retain at least one digit. In the preceding example, the address is written as 21DA: D3: 0: 2F3B: 2AA: FF: FE28: 9C5A after the leading zero bit is removed.

Some addresses may contain long zero-sequence columns. To further simplify the notation, you can also combine adjacent consecutive zero-bit pairs in the colon hexadecimal format, expressed by double colons. The ":" symbol can only appear once in an address. It can also be used to compress the adjacent zero bits in the front and end of the address. For example, the address 1080: 0: 0: 0: 8: 800: 200C: Jun A, 0: 0: 0: 0: 0: 0: 0: 0: 0: 0: 0: 0: 0: 0 can be expressed as the compression format 1080: 8: 800: 200C: 0000a,: 1 ,::.

In IPv4 and IPv6 hybrid environments, it is sometimes more suitable to use another form: x: d. d. d. d, where x is the hexadecimal value of the six high-order 16-bit groups in the address, and d is the standard IPv4 representation of the four low-order 8-bit groups in the address ). For example, the address 0: 0: 0: 0: 0: 13.1.68.3, 0: 0: 0: 0: 0: FFFF: 129.144.52.38 is compressed in the format of: 13.1.68.3 ,:: FFFF.129.144.52.38.

To use a text IPv6 address in a URL, the text address should be closed with the symbols "[" and. For example, the text IPv6 Protocol address FEDC: BA98: 7654: 3210: 7654: FEDC: BA98: 3210: 7654: http: // [FEDC: BA98: 3210: FEDC: BA98: 7654: 3210]: 80/index.html.