TCP/IP

TCP/IP stands for Transmission Control Protocol/ Internet Protocol also known as the Internet Protocol Suite. It serves the industry standard in connecting networks to networks known as the Internet or private networks such as the intranet or extranet around the world.

Operation

TCP is one of the main transport layers of the Internet Protocol Suite. It is an effective transport service connection wherein data is transferred with an end-to-end reliability from the source host to the destination host. TCP verifies the correct delivery of data and provides a support to check for errors and missing data, and re-sends it to complete the data transfer. Meanwhile, IP is the primary component of the Internet Protocol Suite used by all Internet transport protocols such as the TCP to carry data from the source to its destination. Its main functions include addressing, fragmentation and re-assembly of an Internet datagram, type-of-service specification and security information.

Background

During the 1960s, the Defense Advanced Research Project Agency (DARPA) funded research to allow the continuous flow of communication between the Department of Defense (DoD) community; the project resulted in the ARPANET, which became the main foundation for today's Internet. The Internet Protocol Suite of the TCP/IP was the result of the project; it is a key component in the development and growth of the Internet and it was designed by Vinton Cerf and Robert Kahn in 1974 as described by RFC 675, Specification of Internet Protocol Programs. In 1983, TCP/IP became the standard of communication wherein all hosts networks connected to the ARPANET were instructed to convert to the new protocols.

TCP/IP Protocol Layers

The Internet Protocol Suite is composed of different layers of protocols, which include:

• Application Layer- one of the the highest layer of the Internet protocol suite, commonly known as the Internet user protocol, which provides direct service to users, which include Telnet (remote login), FTP (file transfer), and SMTP (electronic mail delivery).
• Transport Layers- provides a reliable end-to-end communication or data transfer for applications. TCP and UDP (User Datagram Protocol) are the main transport layers.
• Internet Layer- The Internet Protocol is the most important component of the layer, which provides the addressing or the routing of a sent data to its destination.
• Link Layer- also known as the media access protocol layer, provides interface to actual networking hardware such as the ethernet or gateways.

Defense Advanced Research Projects Agency