Net 7

The document discusses error detection and correction in data link layers of networks. It describes three types of errors: single bit errors, multiple bit errors, and burst errors. It then explains four common error detecting codes: parity checking, cyclic redundancy check (CRC), longitudinal redundancy check (LRC), and check sums. For error correction, it outlines backward error correction and forward error correction, and provides details on Hamming codes as an example of forward error correction using extra parity bits to allow detection and correction of single errors.