Cyclic redundancy checking

Abstract

While parity checks are useful for low data rates and asynchronous messages where large gaps in between successive bytes make compilation of data into block impossible, for more general protection of data a much more robust error detection scheme is necessary. The cyclic redundancy check or CRC is one such mechanism and it requires that the data are divided into blocks, hence it is termed a block code. As with many block codes the CRC is based on finite field theory which need not concern us greatly, except that there are a few ground rules which must be understood.