Essential Guide to Computing: The Story of Information Technology, The

Error detection and correction

As we have noted, it is not reasonable to assume that information transmitted from A to B or to anywhere else will arrive unchanged. Some mechanism must be implemented to detect and correct errors. There are a variety of successful approaches to doing this, and most are like compression in that they use algorithms to analyze the data—either to detect errors or to both detect and correct them. The algorithms, like those for compression, vary in their accuracy. Not surprisingly, the most accurate are the most complex.

Basic Error Detection/Correction

An example of a low accuracy algorithm is parity checking. In this approach, each bit in a byte is summed to see whether the byte's total is odd or even; if it is even, ...