In the seven-layer OSI model of computer networking, the data link layer is layer 2. The data link layer is the protocol layer that transfers data between adjacent network nodes in a wide area network or between nodes on the same local area network segment.
From Wikipedia:
In the seven-layer OSI model of computer networking, the data link layer is layer 2; in the TCP/IP reference model, it is part of the link layer. The data link layer is the protocol layer that transfers data between adjacent network nodes in a wide area network or between nodes on the same local area network segment. The data link layer provides the functional and procedural means to transfer data between network entities and might provide the means to detect and possibly correct errors that may occur in the physical layer.
