What Is TCP/IP?

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 different protocols, but they both have 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 have IP to work. In order to work, TCP/IP goes through a four-layer process twice.  

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History of TCP/IP

TCP/IP originated in the 1970s when two Defense Advanced Research Projects Agency (DARPA) scientists, Vinton Cerf and 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. 

Layers in TCP/IP  

The four layers of the TCP/IP protocol are data link, internet, transport, and application. 

• 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 involves the parts of the communications the user sees, such as email or a messaging app. 

Is TCP/IP the only internet protocol? 

In addition to TCP/IP, several other types of internet protocols exist, though most work in conjunction with TCP/IP. For example, hypertext transfer protocol (HTTP) involves websites and web browsers. File transfer protocol (FTP) involves sending files across a network. 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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Get on the fast track to a career in IT. In this certificate program, you’ll learn in-demand skills, and get AI training from Google experts. Learn at your own pace, no degree or experience required.

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