All computers connected to the internet must comply with

TCP/IP protocol (Transmission Control Protocol/Internet Protocol) is not a simple protocol, but a set of special protocols, including: TCP, IP, UDP, ARP, etc. These are called subprotocols. Among these protocols, the most important and famous are TCP and IP. Therefore, most network administrators call the entire protocol suite "TCP/IP."

All computers connected to the internet must comply with the TC/IP protocol. The Internet controls data transmission between networks through the TCP/IP protocol. (Recommended learning: PHP video tutorial)

The predecessor of the Internet network, ARPANET, did not use Transmission Control Protocol/Internet Protocol (TCP/IP) at that time. ), but a network protocol called Network Control Protocol (NCP).

However, with the development of the network and the increasing demand of users for the network, designers have discovered that the NCP protocol has many shortcomings and cannot fully support the ARPANET network. In particular, NCP can only be used for isomorphic environment (the so-called homogeneous environment is that all computers on the network run the same operating system), designers believe that the "homogeneous" limitation should not be imposed on a widely distributed network.

In 1980, the TCP/IP protocol for use in "heterogeneous" network environments was successfully developed, which means that the TCP/IP protocol can interoperate on various hardware and operating systems. In 1982, ARPANET began to adopt the TCP/IP protocol.

TCP/IP began with the U.S. Department of Defense, which developed TCP/IP for the Advanced Research Projects Agency Network (ARPAnet, the predecessor of the Internet) in the late 1960s.

The rapid popularity of TCP/IP is due to its low cost, ability to communicate between different platforms and its open nature. "Open" means that software developers can freely use and modify the core protocols of TCP/IP.

TCP/IP is the actual standard adopted by the Internet. UNIX and Linux have always used TCP/IP, and Windows network operating systems also use TCP/IP as the default protocol.

The development of the TCP/IP protocol began in the late 1960s, earlier than the OSI reference model, so it is not very consistent with the OSI reference standard.

Roughly speaking, the TCP protocol corresponds to the transport layer of the OSI reference model, and the IP protocol corresponds to the network layer. Although the OSI reference model is the standard for computer network protocols, there are not many cases where it is actually adopted because of its high overhead.

The TCP/IP protocol is not the case. Because of its simplicity and practicality, it has been widely used. It can be said that the TCP/IP protocol has become the preferred protocol for establishing computer local area networks and wide area networks, and has become a de facto industrial standard and international standard.

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