Layer two, the second lowest layer in the OSI seven layer model. The data link layer splits data into frames (see fragmentation) for sending on the {physical layer} and receives acknowledgement frames. It performs error checking and re-transmits frames not received correctly. It provides an error-free virtual channel to the network layer. The data link layer is split into an upper sublayer, {Logical Link Control} (LLC), and a lower sublayer, {Media Access Control} (MAC). Example protocols at this layer are ABP, Go Back N, SRP. (1995-02-14)
