Data Link Layer

The Data Link Layer is Layer 2 of the OSI reference model and manages data transmission between devices within a common network segment. It processes signals provided by the Physical Layer and organises data into units known as frames. Its core functions include physical addressing through MAC addresses, media access control and the detection of transmission errors. Ethernet is one of the most important technologies operating at this layer. Network devices such as switches primarily operate at Layer 2 and forward frames to the appropriate port based on MAC addresses. The Data Link Layer is commonly divided into the Logical Link Control and Media Access Control sublayers. It therefore provides an essential foundation for structured communication within local Ethernet networks.