Technical Terms and Definitions

Data Link Layer - Telecommunications

The Data-Link Layer is the protocol layer in a program that handles the moving of data in and out across a physical link in a network. The Data-Link Layer is layer 2 in the Open Systems Interconnect (OSI) model for a set of telecommunication protocols.

The Data-Link Layer contains two sublayers that are described in the IEEE-802 LAN standards:

  • Media Access Control (MAC)
  • Logical Link Control (LLC)

The Data-Link Layer assures that an initial connection has been set up, divides output data into data frames, and handles the acknowledgements from a receiver that the data arrived successfully. It also ensures that incoming data has been received successfully by analyzing bit patterns at special places in the frames.