Error Detection and Correction:
Data can be corrupted during transmission. Error detection is used for fault tolerant computing in computer memory, magnetic and optical data storage media, satellite and deep space communications, network communications, cellular telephone networks, and almost any other form of digital data communication. Error coding uses mathematical formulas to encode data bits at the source into longer bit words for transmission. The “code word” can then be decoded at the destination to retrieve the information. The extra bits in the code word provide redundancy that, according to the coding scheme used, will allow the destination to use the decoding process to determine if the communication medium introduced errors and in some cases correct them so that the data need not be retransmitted.
Some applications require that errors be detected and corrected.
Let us first discuss some issues related, directly or indirectly, to error detection and correction.
Topics discussed in this section:
Types of Errors
Detection Versus Correction
Forward Error Correction Versus Retransmission