High-level Data Link Control (HDLC)

The data link layer is the second layer in the OSI seven layer model and its protocols define rules for the orderly exchange of data information between 2 adjacent nodes connected by a data link. Final framing, flow control between nodes, and error detection and correction are added at this layer. In previous chapters the data link layer was discussed in a practical manner. In this chapter its functions will be discussed with reference to HDLC.