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 little 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 organises and sorts all of the data, whilst IP is responsible for sending and receiving it. IP can work with other protocols, but TCP must always have IP to work. To work, TCP/IP goes through a four-layer process twice.  

History of TCP/IP

TCP/IP originated in the 1970s when two Defencee 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 referred to as the internet protocol suite. ARPANET is the predecessor of the internet. 

What is the four-layer process for TCP/IP?  

The four layers of the TCP/IP protocol are datalink, 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 internet layer ensures data arrives safely and accurately. Internet traffic can affect the speed. 

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

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

Is TCP/IP the only internet protocol? 

Several other types of internet protocols exist in addition to TCP/IP, though most of them 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

Getting started in IT support with Coursera 

Nearly every operating system, here in the UK and around the world, relies on TCP/IP. It’s reliable and incorporates mechanisms that help protect data quality. Learning about TCP/IP is only the beginning. 

If you're interested in a career in IT, start today with Google's IT Support Professional Certificate on Coursera. At your own pace, you can earn the certificate and learn the skills required for an entry-level job, including day-to-day IT support tasks, end-to-end customer support, and more. This programme is designed for beginners, and no prior experience is required.