资料来源 : Free On-Line Dictionary of Computing
data link layer
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)