Computer Science – Methods of error detection | e-Consult
Methods of error detection (1 questions)
Two common methods for checking errors after data transmission are parity checking and checksums.
Parity Checking: This method adds an extra bit (the parity bit) to a block of data. The parity bit is set to either 0 or 1 to make the total number of 1s in the data block either even (even parity) or odd (odd parity). The receiver checks the parity of the received data. If the parity is incorrect, it indicates an error has occurred.
Parity checking is most effective at detecting single-bit errors. It can often miss errors caused by multiple bits being corrupted.
Checksums: A checksum is a more sophisticated error detection method. It involves calculating a value (the checksum) from the data being transmitted. This checksum is sent along with the data. The receiver recalculates the checksum from the received data and compares it to the received checksum. If the checksums don't match, an error is detected.
Checksums are effective at detecting burst errors, which are errors that occur in consecutive data bits. They are also more reliable than parity checking for detecting multiple errors.
Method | How it Works | Errors Detected | ||
| Parity Checking | Adds a parity bit to make the number of 1s even or odd. Receiver checks the parity. | Single-bit errors |
| Checksums | Calculates a value from the data and sends it. Receiver recalculates and compares. | Burst errors, multiple errors |