Error Detection Code Wikipedia
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citations to reliable sources. Unsourced material may be challenged and removed. (August 2008) (Learn how and error detection code in digital electronics when to remove this template message) In information theory and
Crc Error Detection Code In C
coding theory with applications in computer science and telecommunication, error detection and correction or error error detection definition control are techniques that enable reliable delivery of digital data over unreliable communication channels. Many communication channels are subject to channel noise, and thus errors
Error Detection And Correction Definition
may be introduced during transmission from the source to a receiver. Error detection techniques allow detecting such errors, while error correction enables reconstruction of the original data in many cases. Contents 1 Definitions 2 History 3 Introduction 4 Implementation 5 Error detection schemes 5.1 Repetition codes 5.2 Parity bits error detection and correction using hamming code example 5.3 Checksums 5.4 Cyclic redundancy checks (CRCs) 5.5 Cryptographic hash functions 5.6 Error-correcting codes 6 Error correction 6.1 Automatic repeat request (ARQ) 6.2 Error-correcting code 6.3 Hybrid schemes 7 Applications 7.1 Internet 7.2 Deep-space telecommunications 7.3 Satellite broadcasting (DVB) 7.4 Data storage 7.5 Error-correcting memory 8 See also 9 References 10 Further reading 11 External links Definitions[edit] The general definitions of the terms are as follows: Error detection is the detection of errors caused by noise or other impairments during transmission from the transmitter to the receiver. Error correction is the detection of errors and reconstruction of the original, error-free data. History[edit] The modern development of error-correcting codes in 1947 is due to Richard W. Hamming.[1] A description of Hamming's code appeared in Claude Shannon's A Mathematical Theory of Communication[2] and was quickly generalized by Marcel J. E. Golay.[3] Introduction[edit] The general idea for achieving error detection
computer data storage that can detect and correct the most common kinds of internal data corruption. ECC memory is used in most computers where data corruption cannot
Error Correction Code
be tolerated under any circumstances, such as for scientific or financial computing. Typically,
Error Correction And Detection
ECC memory maintains a memory system immune to single-bit errors: the data that is read from each word is always error detection and correction in computer networks the same as the data that had been written to it, even if one or more bits actually stored have been flipped to the wrong state. Most non-ECC memory cannot detect errors https://en.wikipedia.org/wiki/Error_detection_and_correction although some non-ECC memory with parity support allows detection but not correction. Contents 1 Problem background 2 Solutions 3 Implementations 4 Cache 5 Registered memory 6 Advantages and disadvantages 7 References 8 External links Problem background[edit] Electrical or magnetic interference inside a computer system can cause a single bit of dynamic random-access memory (DRAM) to spontaneously flip to the opposite state. It was initially https://en.wikipedia.org/wiki/ECC_memory thought that this was mainly due to alpha particles emitted by contaminants in chip packaging material, but research has shown that the majority of one-off soft errors in DRAM chips occur as a result of background radiation, chiefly neutrons from cosmic ray secondaries, which may change the contents of one or more memory cells or interfere with the circuitry used to read or write to them.[2] Hence, the error rates increase rapidly with rising altitude; for example, compared to the sea level, the rate of neutron flux is 3.5 times higher at 1.5km and 300 times higher at 10–12km (the cruising altitude of commercial airplanes).[3] As a result, systems operating at high altitudes require special provision for reliability. As an example, the spacecraft Cassini–Huygens, launched in 1997, contains two identical flight recorders, each with 2.5gigabits of memory in the form of arrays of commercial DRAM chips. Thanks to built-in EDAC functionality, spacecraft's engineering telemetry reports the number of (correctable) single-bit-per-word errors and (uncorrectable) double-bit-per-word errors. During the first 2.5years of flight, the spacecraft reported a nearly constant single-bit error rate of about 280errors per day. However, on November 6, 1997, during t
of 6 total. C ► Capacity-achieving codes (1 P) ► Capacity-approaching codes (5 P) ► Checksum algorithms https://en.wikipedia.org/wiki/Category:Error_detection_and_correction (2 C, 27 P) ► Cyclic redundancy checks (4 P) H ► Hash functions (3 C, 15 P) M ► Message authentication codes (15 P) Pages in category "Error detection and correction" The following 122 pages are in this category, out of 122 total. This list may not reflect recent changes error detection (learn more). Error detection and correctionA Acknowledgement (data networks) Alternant code AN codes Automated quality control of meteorological observations Automatic repeat requestB BCH code BCJR algorithm Berger code Berlekamp–Massey algorithm Berlekamp–Welch algorithm Binary Golay code Binary Reed-Solomon Bipolar violation Burst error-correcting codeC Casting out nines Certifying algorithm Check digit error detection code Chien search Chipkill Coding gain Coding theory Concatenated error correction code Confidential incident reporting Constant-weight code Convolutional code Coset leader Cosine error effect Cross-interleaved Reed–Solomon codingD Data Integrity Field Data scrubbing Detection error tradeoff Drop-out compensator Dual modular redundancyE Echo (computing) Enumerator polynomial Error concealment Error correction mode Error correction model Error floor Error-correcting codes with feedback EXIT chart Expander codeF File verification Folded Reed–Solomon code Forney algorithm Forward error correction Forward–backward algorithmG Generalized minimum-distance decoding Go-Back-N ARQ Group code recordingH Hadamard code Hagelbarger code Hamming code Hamming(7,4) Hash calendar Hash function Hash list Header check sequence Homomorphic signatures for network coding Hybrid automatic repeat requestI IPv4 header checksum ISO 7064 Iterative Viterbi decodingJ Justesen codeK K-independent hashingL Latin square Lexicographic code List decoding Locally decodable code Locally testable code Long code (mathematics) Longitudinal redundancy check Low-density parity-check code Luhn algorithmM Majority logic decoding Maximum likelihood sequence estimation Memory ProteX