OSI Reference Model

The OSI Reference Model is a framework that helps understand how different networking protocols communicate. It has seven layers, each with specific functions: 1. **Physical** - Handles raw data transmission. 2. **Data Link** - Manages error detection and correction. 3. **Network** - Routes data between devices. 4. **Transport** - Ensures complete data transfer. 5. **Session** - Manages sessions between applications. 6. **Presentation** - Translates data formats. 7. **Application** - Interfaces directly with user applications. Each layer serves distinct roles, making it easier to troubleshoot and design networks by isolating issues to specific layers.