What does ipv4 mean?
Internet Protocol version 4 (English: Internet Protocol version 4, IPv4), also known as the fourth version of the Internet Communication Protocol, is the fourth revised version of the Internet Protocol in the development process, and it is also the fourth version of this protocol. A widely deployed version. IPv4 is the core of the Internet and the most widely used version of the Internet Protocol. Its successor version is IPv6. Until 2011, when the IANA IPv4 addresses were completely exhausted, IPv6 was still in the early stages of deployment.
IPv4 is described in RFC 791 published by the IETF in September 1981, which replaced RFC 760 published in January 1980.
IPv4 is a connectionless protocol that operates on the link layer (such as Ethernet) using packet switching. This protocol delivers packets on a best-effort basis, meaning that it does not guarantee that any packet will reach its destination or that all packets will arrive in the correct order without duplication. These aspects are handled by upper-layer transport protocols (such as Transmission Control Protocol).
On November 26, 2019, all 4.3 billion IPv4 addresses in the world have been allocated, which means that there are no more IPv4 addresses to be allocated to ISPs and other large network infrastructure providers.
Extended information:
IPV4 address format
IPv4 address can be written in any form that represents a 32-bit integer value, but in order to facilitate human reading and analysis, it is usually Written in dotted decimal form, that is, four bytes are written separately in decimal notation, separated by dots.
In dotted decimal format, the value is 192.0.2.235; in dotted hexadecimal format, the value is 0xC0.0x00.0x02.0xEB. Each byte is converted to hexadecimal separately; dot In octal format, the value is 0300.0000.0002.0353; in hexadecimal format, the value is 0xC00002EB. Connect the dotted hexadecimal numbers together.
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