IP addresses can be divided into two categories: static IP addresses and dynamic IP addresses. Let’s take a look at the specific contents of static IP addresses and dynamic IP addresses.
Static IP Address
Static IP addresses usually do not change, but may change due to network management. They serve as permanent Internet addresses, providing a simple and reliable way to communicate. From the static IP address of a system, we can obtain many details such as the continent, country, region and city where the computer is located, the Internet Service Provider (ISP) that services that specific computer, and non-technical information such as the precise country latitude and longitude, as well as the area of the computer.
Dynamic IP Address
Dynamic IP address is the second category. These are temporary IP addresses. These IP addresses are assigned to computers every time they connect to the Internet. They are actually borrowed from a pool of IP addresses and shared across different computers. Since there are a limited number of static IP addresses available, ISPs often reserve a portion of the addresses assigned to them to be shared this way among users.
Static IP addresses are considered less secure than dynamic IP addresses because they are easier to track.
The two versions of IP addresses currently running are IP version 4 (IPv4) and IP version 6 (IPv6).
IP Version 4 (IPv4)
IPv4 uses 32-bit IP addresses. Therefore, the maximum number of IP addresses is 2 32 or 4,294,967,296. That's more than 4 billion IP addresses. IPv4 addresses are usually formatted into four 8-bit fields. Each 8-bit field represents one byte of the IPv4 address.
The IPv4 addressing system is divided into five categories of IP addresses. All five classes are identified by the first octet of the IP address.
The different categories of IPv4 addresses are as follows:
1) Class A address
2) Class B address
3) Class C address
4) Class D address
5) Class E address
IP version 6 (IPv6)
IPv6 is the latest version of the Internet protocol. With the rapid development of the Internet, there is a global shortage of IPv4. IPv6 was developed by the Internet Engineering Task Force (IETF). IPv6 is designed to replace IPv4. IPv6 uses 128-bit addresses, which allows 2128, which is approximately 3.4×1038 addresses. The actual number is slightly smaller because some ranges are reserved for special purposes or are unused. IPv6 addresses are represented by 8 groups of four hexadecimal digits, with groups supported by colons. An example is given below:
For example: 2001:0db8:0000:0042:0000:8a2e:0370:7334
The above is the detailed content of IP addresses are divided into several categories. For more information, please follow other related articles on the PHP Chinese website!