TCP / IP Protocol Explanations

TCP / IP protocol. Set of network protocols on which the Internet is based and that allow the transmission of data between computer networks. Sometimes it is called the TCP / IP protocol suite, in reference to the two most important protocols that make it up: Transmission Control Protocol (TCP) and Internet Protocol (IP), which were the first two to be defined, and which they are the most used of the family. There are so many protocols in this set that there are more than 100 different ones, among them is the popular HTTP (HyperText Transfer Protocol), which is the one used to access web pages, in addition to others such as ARP (Address Resolution Protocol) for address resolution, FTP (File Transfer Protocol) for file transfers, and SMTP (Simple Mail Transfer Protocol) and POP (Post Office Protocol) for email, TELNET for accessing remote computers, among others.

According to Abbreviationfinder, TCP / IP is the foundation of the Internet, and is used to link computers using different operating systems, including PCs, minicomputers, and mainframes over local area (LAN) and wide area (WAN) networks.

History of the TCP / IP Protocol

The Internet Protocol Family was the result of work carried out by the Defense Advanced Projects Research Agency (DARPA) in the early 1970s. After the construction of the pioneering ARPANET in 1969 DARPA began to work on a large number of data transmission technologies. In 1972, Robert E. Kahn was hired by DARPA’s Office of Information Processing Techniques, where he worked on packet communication by satellite and radio waves., recognized the important value of communicating in these two ways. In the spring of 1973, Vint Cerf, developer of the ARPANET protocol, Network Control Program (NPC) joined Kahn with the aim of creating an open interconnection architecture and thus designing the new generation of ARPANET protocols.

By the summer of 1973, Kahn and Cerf had achieved a fundamental overhaul, where the differences between the network protocols were hidden using a Communications Protocol and furthermore, the network was no longer responsible for the reliability of the communication, as happened in the ARPANET, it was the host who was responsible. Cerf recognized the merit of Hubert Zimmerman and Louis Pouzin, creators of the CYCLADES network, as their work was greatly influenced by the design of this network.

A computer called a router (name that was later changed to gateway, to avoid confusion with other types of Gateway) is equipped with an interface for each network, and sends Datagram back and forth between them. The requirements for these routers are defined in the RFC 1812 document.

This idea was put into practice in a more detailed way by the research group that Cerf had at Stanford during the period from 1973 to 1974, resulting in the first TCP specification (Request for Comments 675,) Then DARPA was hired by BBN Technologies, Stanford University, and University College London to develop operational versions of the protocol on different hardware platforms. Four different versions were thus developed: TCP v1, TCP v2, a third split into two TCP v3 and IP v3 in the spring of 1978, and later the TCP / IP v4 version was stabilized – the standard protocol still used on the Internet.

In 1975, the first communication test between two networks with TCP / IP protocols was carried out between Stanford University and University College London (UCL). In 1977, another communication test was conducted using a TCP / IP protocol between three different networks with locations in the United States, United Kingdom, and Norway. Several different prototypes of TCP / IP protocols were developed at multiple research centers between 1978 and 1983. The complete migration of the ARPANET network to the TCP / IP protocol was officially concluded on January 1, 1983 when the protocols were permanently activated.

In March of 1982, the United States Department of Defense declared TCP / IP protocol standard for communications between networks militares.En 1985, the Management Center (Internet Architecture Board IAB for its acronym in English) organized a Three-day Workshop, which was attended by 250 commercials promoting the protocol, which contributed to an increase in its commercial use.

Kahn and Cerf were awarded the Presidential Medal of Freedom on November 10, 2005 for their contribution to American culture.

On January 1, 2010, the TCP / IP Protocol turned 27 years old.

TCP packet structure

A TCP packet is encapsulated by the TCP header that specifies the routing, such as the addresses and destination of the datagram and consists of the fields:

  • Port of origin.
  • Port of destination.
  • Sequence number.
  • Confirmation number.
  • Data scrolling.
  • A reserved field.
  • Control bit.
  • Urgency indicator.

IP packet structure

IP is the protocol in charge of classifying and delivering packets. Each incoming or outgoing IP packet is called a datagram. The IP protocol generates datagrams by encapsulating the payload with the source IP address of the sender and the IP address of the recipient. The IP datagramconsists of the following fields:

  • Header length.
  • Priority and type of service.
  • Total length.
  • Summary of indicators.
  • Scroll fragment.
  • Time of life.
  • Destination address.
  • Options and filling.


  • The TCP / IP suite is designed for routing and has a very high degree of reliability, suitable for large and medium networks, as well as business networks. It is used globally to connect to the Internet and web servers. It is compatible with standard tools for analyzing network performance.


  • TCP / IP is more difficult to configure and maintain than NetBEUI or IPX / SPX; it is also somewhat slower in networks with a low medium volume of traffic. However, it can be faster on high-traffic networks where a large number of frames have to be routed.

Practical application

  • TCP / IP is used both in business networks such as on university campuses or in business complexes, where they use many routers and connections to mainframe or UNIX computers, as well as in small or home networks, and even in mobile phones and home automation.