The OSI model (Open Systems Interconnection model) is a conceptual model that describes how data is transmitted and received over a network. It was developed by the International Organization for Standardization (ISO) in the early 1980s as a framework for understanding network communication.
The OSI model is divided into seven layers, each of which is responsible for a specific aspect of network communication. These layers are:
This layer is responsible for the physical transmission of data, including the electrical, mechanical, and physical specifications of the network medium.
This layer is responsible for transmitting data over a physical link, including the formatting of data packets and error correction.
This layer is responsible for routing data between different networks, including addressing, routing, and congestion control.
This layer is responsible for ensuring the reliable transmission of data between hosts, including error recovery, flow control, and congestion control.
This layer is responsible for managing the communication sessions between applications, including establishing, managing, and terminating sessions.
This layer is responsible for presenting data to the application layer in a meaningful way, including encryption, compression, and data conversion.
This layer is responsible for providing access to network services for applications, including email, file transfer, and remote login.
The OSI model provides a framework for understanding network communication, and it is often used as a reference model for the development of networking standards and protocols.
