The Open Systems Interconnection (OSI) Model is a conceptual framework that defines the steps and processes required for communication between different computer systems. It is a standardized model developed by the International Organization for Standardization (ISO) to facilitate interoperability between different network devices and protocols.
The OSI Model consists of seven layers, with each layer responsible for a specific function in the communication process. These layers are:
1. Physical Layer: This layer deals with the physical transmission of data over the network, including the electrical, mechanical, and physical specifications.
2. Data Link Layer: It handles the reliable and error-free transmission of data frames between adjacent nodes, ensuring the integrity of the data.
3. Network Layer: This layer allows for the routing of data packets across different networks, taking care of logical addressing and establishing connections.
4. Transport Layer: Responsible for end-to-end communication between hosts, managing flow control, error recovery, and segmentation/reassembly of data.
5. Session Layer: Provides mechanisms for establishing, maintaining, and terminating communication sessions between applications.
6. Presentation Layer: Handles the translation, encryption, and compression of data, ensuring that the data is in a format that the application layer can understand.
7. Application Layer: The topmost layer where the actual user applications reside, allowing them to interact with the network services.
The OSI model serves as a guideline for designers and developers in creating network protocols and applications that can operate independent of the underlying hardware and software, thus enabling seamless communication between different systems.
