Summary data link layers

The Data Link Layer is the second layer of the OSI model, responsible for ensuring reliable data transfer across a physical link between two devices. Its main functions include: Framing: Organizes raw bits into frames for transmission. Addressing: Uses MAC addresses to identify devices on a local network. Error Detection: Identifies and corrects transmission errors (e.g., via CRC). Flow Control: Regulates data flow to prevent overwhelming the receiver. Medium Access Control (MAC): Manages device access to the shared communication medium. Collisions Handling: Detects and resolves data collisions in the network. The layer has two sublayers: LLC (Logical Link Control): Manages error control and flow. MAC (Media Access Control): Controls access to the physical transmission medium. Common protocols include Ethernet, Wi-Fi (IEEE 802.11), and PPP.