OSI Layer Data Link

In short: Layer 2 of the OSI model (data link layer) ensures transmission between directly connected devices.

In more detail: Data is packed into frames and given MAC addresses. A checksum (CRC) detects transmission errors.

In Depth

Devices and protocols

Switches and bridges, Ethernet, Wi-Fi, VLAN, ARP, MAC addresses.

Access methods

CSMA/CD (Ethernet) and CSMA/CA (Wi-Fi). See OSI layers, frames.

See also: OSI Layers, Switch, MAC Addresses, Frames