rétegmodell

The rétegmodell, also known as the OSI (Open Systems Interconnection) model, is a conceptual framework used to understand and design the functions of communication systems. It was developed by the International Organization for Standardization (ISO) in 1984. The model divides the communication process into seven distinct layers, each with specific functions and protocols. This layered approach allows for modular development and troubleshooting of communication systems.

The seven layers of the rétegmodell are as follows:

1. Physical Layer: Deals with the transmission and reception of unstructured raw data over a physical medium. It defines electrical, mechanical, procedural, and functional interfaces to activate, maintain, and deactivate physical links between network nodes.

2. Data Link Layer: Provides node-to-node data transfer and handles error correction from the physical layer. It ensures reliable point-to-point and point-to-multipoint connections in a network.

3. Network Layer: Responsible for path determination and logical addressing. It routes data packets from the source to the destination across multiple networks.

4. Transport Layer: Provides end-to-end communication services for applications. It ensures complete data transfer and handles error recovery and flow control.

5. Session Layer: Manages and controls the connections between computers. It establishes, maintains, and terminates sessions between applications.

6. Presentation Layer: Translates data between the application layer and the network format. It handles data encryption, compression, and translation.

7. Application Layer: Provides network services directly to end-users and applications. It supports file transfers, email, and other network software services.

The rétegmodell is a theoretical model and does not correspond directly to any specific protocol or product. However, it serves as a useful reference for understanding and designing communication systems.