Error Detection and Correction Codes

In the realm of computer science error detection and correction codes or techniques play crucial role in terms of enabling reliable delivery of digital data over unreliable communication channels. During transmission or when receiving data the communication channels are subjected to factors like channel noise which pave way for errors. Error detection techniques permit identifying such errors, while error correction enables reconstruction of the original data.

Introduction of errors and reconstructing

Error detection can be defined as either detection of errors caused by noise or other impairments during transmission or detection of errors and reconstruction of the original, error free-data. Error correcting code is an algorithm to express a sequence of numbers in a specific way so that errors that are introduced can be detected and corrected. Error coding adapts mathematical formulas to encode data bits at the source into longer bit words for transmission. Different error coding schemes are selected depending upon the types or errors expected as well considering the communication medium’s expected error rate and if data transmission is possible.

The processors which are faster and communications technology produce complex coding schemes for better detecting and correcting capabilities possible for smaller embedded systems and permitting for more robust communications.

Reliable digital data transmission

Error detecting and correction code is a method of providing reliable digital data transmission and storage when the communication medium used has an unacceptable bit error rate and a low signal to noise ratio. This error coding is used on many of the digital applications such as computer memory, magnetic and optical data storage media, satellite and deep space communications, network communications and cellular telephone networks. The data is encoded with extra bits at the source than transmitting digital data in a raw bit for bit form. The receiver can code decode it to retrieve the desired information is transmitted through the longer code. The data is transformed by the extra bits into a valid code word in the coding scheme.

Error detection schemes

Error detecting schemes are available in the means such as repetition codes, parity bits, check sums, cyclic redundancy checks and cryptographic hash functions. And whereas the error correction would include methods like Automatic repeat request, error correcting code and hybrid schemes. Error detection and corrections codes are performed to enhance the reliability of data storage media. Dynamic random access memory perhaps offers increased protection against soft errors by depending on error correcting codes.

Questions:

• What is meant by error detecting and correction codes?
• State the importance of error detection and correction codes.