TCP or Transmission Control Protocol is a set of protocols which helps to communicate among devices over the internet. TCP offers a better way to exchange information among applications which contains numbered and error-free group of data packets.


TCP is one of the most used communication protocol for digital communications. It defines how automated devices can connect to the network and exchange data between them. TCP/IP is important because the whole internet runs over it. This protocol allows two distinct networks to communicate with one another. In the absence of TCP, data transmission among devices might not be possible.

Transmission Control Protocol is a communication protocol to create as well as a support information exchange among various applications over the local networks or the Internet. TCP/IP networking model was first used in 1974 by Vint Cerf and Bob Kahn, while working with Gérard Le Lann. They were trying to exchange data packets over the network.

Network Protocol

TCP is one of the most common protocols in a digital communications network which operates with Internet Protocol, hence is also quoted as TCP/IP suite. In the OSI layer, TCP works in the transport layer to create a connection with remote devices to ensure that devices can transmit data packets with each other.

How TCP works?

A common and simple example of how TCP works can be requesting a web page on your computer. On requesting a web page on a web browser, the computer dispatches TCP packets to the web server. It then requests to convey the web page, in exchange. The web server sends back a group of TCP data packets. Web browser group these packets together to display the requested web page. TCP follows a similar process when you click a link, post a comment and so on.

How TCP works?

TCP exchange sorted and reviewed information every time. The packets are sorted based on the initial number assigned to them and are delivered to the destination. Another important feature of TCP is the error-check where the recipient sends an acknowledgement to the sender after receiving the data packets. If the data is not received by the recipient then the sorted data packets are resent by the sender in the same order.

A TCP consists of a header and a data segment. The header consists of ten required sections and one optional extension section. After the header, there is a data segment which contains the transferred data in the application. TCP header does not contain the data segment length.

Why TCP is one of the Most Reliable Internet Protocols?

Why TCP is one of the Most Reliable Internet Protocols?
  • It offers end-to-end distribution of data packets between different nodes. It works with Internet Protocol to define the logical position of a remote point. Hence, the transmission control protocol can transport and protects the accurate data exchange.
  • It split large data packets into smaller units to maintain the integrity of the data and then reassemble them in the initial sequence to deliver it to the recipient.
  • TCP is a connection-oriented protocol, as it establishes and maintains a connection till the data exchange between the applications is complete.
  • TCP ensures error-free data transmission by handling retransmission of distorted or dropped data packets based on the acknowledgement received from the recipient.
  • Transmission control protocol tracks the data when used to transfer information to avoid data loss or corrupted data. In case of a network error, it sends an error message to the sender about the loss of connection with the destination node.

If you have read till the end, then you might have got a basic understanding of networking and digital communication using TCP/IP. This can help you to recognise and improve vulnerabilities in your connected ecosystem.