TCP/IP Reference Model

Table of Contents hide

History of TCP/IP Reference Model

TCP/IP Reference Model was created in the 1970s by DARPA(Defense Advanced Research Project Agency), an agency of the United States Department of Defense.
It laid the foundation for ARPANET(Advanced Research Project Agency Network), which was the world’s first wide area network and a predecessor of the Internet.

It is the foundation of the Internet Protocol Suite, commonly known as TCP/IP (Transmission Control Protocol/Internet Protocol).
This model, though simpler than the OSI model, is widely adopted due to its flexibility and the way it facilitates real-world networking applications.

The TCP/IP Reference Model is a simplified, practical framework that outlines how various network protocols interact to allow devices to communicate over networks, particularly the Internet.
The TCP/IP Model is a popular specification for computer network protocols. It helps to control, coordinate, and regulate the proper functioning of a typical computer network by providing different types of protocols as needed by its various layers.
The TCP/IP Reference Model is a streamlined, practical approach to networking that has been the backbone of the Internet. Its four layers—Link, Internet, Transport, and Application—allow data to be transferred between devices across different networks in a scalable and efficient manner.

There are the following common features performed by the TCP/IP model –

End-to-End Functioning
- The design of TCP/IP emphasizes that most of the control and functionality should be handled at the end hosts (e.g., error detection, and data integrity). Intermediate network devices (e.g., routers) focus on routing and forwarding packets.
Statelessness Transmission
- Each packet is treated independently, and routers do not need to maintain information about ongoing sessions, simplifying network management.
Flexibility and Scalability
- TCP/IP supports a wide range of devices and networks, allowing for the creation of the massive global internet.
- It is highly scalable, making it suitable for small local networks or global wide-area networks.
Best-Effort Delivery
- IP, the primary protocol in the Internet Layer, provides best-effort delivery without guarantees.
- Higher layers of this model(e.g., TCP) provide reliability if needed.

TCP/IP is typically divided into four layers (from bottom to top) –
- Link/Network Interface(Access) Layer (Layer 1)
- Internet/Network Layer (Layer 2)
- Transport Layer (Layer 3)
- Application Layer (Layer 4)