Error coding

Abstract

The data transmitted over communications channels, and the Internet must be protected against or detect errors. Error bits are added to data either to correct or to detect transmission errors. Normally, the more bits that are added, the better the correction or detection. Error detection allows the receiver to determine if there has been a transmission error. It cannot rebuild the correct data and must either request a retransmission or discard the data. With error correction, the receiver detects an error and tries to correct as many error bits as possible. Again, the more error coding bits are used, the more bits can be corrected. An error correction code is normally used when the receiver cannot request a retransmission.