What is network stack?

The network stack is a collection of software layers that work together to provide network communication in a computer system. The layers of the network stack are responsible for managing various aspects of network communication, including data transmission, packet routing, error detection and correction, protocol implementation, network security, and more.

The network stack is typically divided into five or seven layers, depending on the model being used. The most common model is the seven-layer OSI (Open Systems Interconnection) model, which includes the following layers:

1. Physical layer: This layer is responsible for the physical transmission of data over the network, including things like cables, connectors, and other hardware.

2. Data link layer: This layer controls the flow of data between two connected devices and includes error detection and correction mechanisms.

3. Network layer: This layer is responsible for routing data between different networks and includes protocols such as IP (Internet Protocol).

4. Transport layer: This layer provides reliable data transfer between applications running on different devices and includes protocols such as TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).

5. Session layer: This layer establishes and manages connections between applications running on different devices.

6. Presentation layer: This layer transforms data into a format that can be understood by different applications.

7. Application layer: This layer provides network services to applications running on different devices and includes protocols such as HTTP (Hypertext Transfer Protocol), SMTP (Simple Mail Transfer Protocol), and FTP (File Transfer Protocol).

Overall, the network stack is a crucial component of any computer system that needs to communicate over a network, and it is designed to ensure efficient, reliable, and secure data transfer.