TCP/IP is an acronym for “Transmission Control Protocol/Internet Protocol,” which is practically the reason why the Internet works. These protocols let computers communicate with one another over the Web.

TCP takes enormous amounts of data, compiles them into network packets (i.e., the units of data transmitted over the Internet), and sends them to another computer’s TCP. Think of TCP as the Internet’s “delivery man,” and the “package” he delivers is the data in the form of packets.

IP on the other hand, is the delivery man’s Global Positioning System (GPS). It ensures that the right locations (i.e., computers or devices) receive the network packets.

Because of TCP/IP, people from Europe can check what’s happening on the other side of the world, and vice versa.

Other interesting terms…

Read More about “TCP/IP”

You may encounter some technology experts referring to TCP/IP as the IP suite, and that is true. This suite is made up of other communication protocols besides TCP and IP. However, since they were the first two protocols developed to make the Internet work, the Internet protocol suite came to be known as “TCP/IP.”

The TCP/IP model has four layers—the link layer, the Internet layer, the transport layer, and the application layer—all of which work together to transmit data over the Internet successfully.

Brief History of TCP/IP

The U.S. Department of Defense was responsible for developing the model in the 1970s through the Defense Advanced Research Projects Agency (DARPA). The DARPA scientists who designed the model were Vint Cerf and Bob Kahn. The ARPANET, the earliest version of the Internet, was the first to use the protocols. As such, Cerf and Kahn are considered the “fathers of the Internet.”

At present, the Internet Engineering Task Force (IETF) manages TCP/IP and the rest of the components of the IP suite.

How Does TCP/IP Work?

TCP/IP connections are divided into four layers of a standard process, regardless of the hardware or software used. Getting to know these layers is the key to understanding how TCP/IP works. The four layers are:

  • Application layer: This refers to any program that exchanges information. If you’re reading this article on Google Chrome, then you’re on this layer. An application layer could refer to a browser, a server, an application, or any platform whose job is to send files and information to the transport layer.
  • Transport (TCP) layer: This layer’s primary purpose is to figure out how the information from the application layer should be sent to the destination. In it, the data is broken down into network packets.
  • Internet (IP) layer: After the information is converted into packets, it is sent to the IP layer. This layer is tasked to assign an IP address to each network packet so it can be sent to the exact location of a specific network. The IP layer then sends the packets to the correct destination through the network interface.
  • Network interface: This is also known as the “data link layer (DLL),” “link layer,” or “physical layer.” Whatever term you use, this layer handles the data’s movement from sender to receiver through a wireless network, an Ethernet cable, and other physical parts that allow information to travel.

To better understand how TCP/IP works, watch the video below that likens TCP/IP to sending a puzzle to a friend.

Features of TCP/IP

The model has become the industry standard because it has features that make connectivity possible. Among its features are:

1. Interoperability

Almost all operating systems (OSs) have TCP/IP support. So it doesn’t matter if you’re using a Windows computer and accessing files from a server that runs on Linux or vice versa, communication between the two different OSs will still work.

2. No Single Vendor

Since no single organization owns the model, anyone can implement it in its products, be it hardware or software.

3. Routability

Because TCP/IP is routable, it allows the transport of packets of data from one network to another.

4. Error and Flow Control

The model can check for any transmission error and resend data when such is detected. This feature ensures the reliability and accuracy of the data transmitted.

5. Support for Different Applications

One computer may be running various network applications, so TCP/IP makes sure that the right packets reach the correct application. Ports and port numbers that identify which parts of hardware an application (i.e., the data’s intended recipient) should be connected to make this possible.

Key Takeaways

  • TCP/IP enables Internet communication between computers.
  • The U.S. Department of Defense developed it in the 1970s.
  • TCP handles data by breaking it into network packets, while IP ensures these reach the correct destinations.
  • The TCP/IP model consists of four layers—link layer, Internet layer, transport layer, and application layer—all working together to transmit data.
  • TCP/IP is known for its interoperability, lack of a single controlling organization, routability, error and flow control, and support for various applications.