The 7 Layer Of The OSI Model

The 7 layer of the OSI (Open System Interconnection) model:

1. Physical layer ; Physical layer: cable, fiber, air, ... is responsible for mechanical characteristics (connectors), electrical characteristics, functional characteristic (modulation schemes, tranamission rate, ...)
2. Data link layer ; Data link layer: controls data transfer between 2 network elements (directly connected), manages flow control, controls error detection and correction (CRC), manages transmission
3. Network layer ; Network layer: provides addressing information to guide the data through the network from the sender terminal to the data receiver location, routing, defines safety ways to securize the network
4. Transport layer ; Transport layer: controls the end-to-end message transport across the network, provides the last error detection and correction, multiplexes the informations
5. Session layer ; Session layer: establishes the commencement (log-on) and completion (log-off) of a "session" between applications, synchronisation, priority management
6. Presentation layer ; Presentation layer: data set format, data compression, data rate transmission
7. Application layer ; Application layer: interface between the network and the application, provides specific services ex: file tranfer, remote recording, ...