What Is TCP/IP?

Key takeaways

• TCP/IP is an internet protocol that breaks data into packets and transmits them, allowing computers to communicate with one another across long distances.

• The TCP/IP model is made of four layers: data link, network, transport, and application.

• TCP/IP stands for transmission control protocol/internet protocol.

Internet protocols like TCP/IP matter because they let computers communicate with one another. Read on to discover more about TCP/IP, including what it is, its history, and its different layers.

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What does TCP/IP stand for?

TCP/IP stands for transmission control protocol/internet protocol. It's an internet protocol that allows computers to communicate with one another and transfer data across long distances. The protocol breaks data down into packets and transmits them to its destination. Once it arrives, it puts them back together into one clear message.

Technically, TCP and IP are two distinct protocols, but both play important roles. TCP organizes and sorts all the data, while IP is responsible for sending and receiving it. IP can work with other protocols, but TCP must always use IP. To work, TCP/IP goes through a four-layer process twice.

History of TCP/IP

TCP/IP originated in the 1970s when two Defense Advanced Research Projects Agency (DARPA) scientists, Vinton Cerf and Robert (Bob) Kahn, created it. It was initially the standard protocol for the Advanced Research Projects Agency Network (ARPANET) and is sometimes called the internet protocol suite. ARPANET is the predecessor of the internet.

TCP/IP layers explained

The four layers of the TCP/IP protocol are data link, internet, transport, and application. Explore these four layers in more detail below:

• The data link layer is sometimes called the link layer, network interface layer, network access layer, or physical layer. It involves the physical components of computer-to-computer communication, like the wireless network, Ethernet cable, and network interface card.

• The network layer ensures data arrives safely and accurately. Internet traffic can affect the speed.

• The transport layer divides the data into packets and ensures they reach their destination.

• The application layer includes the parts of communication that the user sees, such as email or a messaging app.

Read more: What Are Data Packets?

Is TCP/IP the only internet protocol?

In addition to TCP/IP, the internet uses several other types of protocols, though most work in conjunction with TCP/IP. For example, the hypertext transfer protocol (HTTP) is used by websites and web browsers. The file transfer protocol (FTP) sends files across a network. The simple mail transfer protocol (SMTP) focuses on sending and receiving emails.

Related terms

• DHCP

• Social engineering

• Binary code

• IT infrastructure

• Public key

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