Computer Science – 6.2 Data Integrity | e-Consult
6.2 Data Integrity (1 questions)
Data transfer involves moving data from one location to another, which can introduce errors. Data verification methods during transfer are essential to ensure data integrity. Here are three methods:
- Error Detection Codes (e.g., Parity Checks, CRC): These codes are added to the data before transmission. The receiver uses the code to detect errors that occurred during transmission. Parity checks are simple, while Cyclic Redundancy Checks (CRC) are more robust.
- Checksums/Hashing: Similar to data entry, a checksum or hash value is calculated before transmission and verified upon reception. If the checksums don't match, the data is considered corrupted.
- Data Reconciliation: The data is transferred to a backup location, and the two datasets are compared. Any discrepancies are investigated and corrected. This is particularly useful when transferring large datasets over networks.
Advantages: Can detect common types of transmission errors. Relatively easy to implement. Provides a degree of data integrity.
Disadvantages: May not detect all types of errors, especially burst errors (multiple consecutive bit errors). Adds overhead to the data being transmitted. CRC codes can be computationally intensive.
Advantages: Detects data corruption during transmission. Relatively quick to calculate and verify. Provides a reliable indication of data integrity.
Disadvantages: Only detects data corruption, not errors in the original data. Doesn't identify the specific error. Requires a reliable checksum algorithm. Not suitable for all data types.
Advantages: Can detect a wide range of errors, including data corruption, incomplete transfers, and data loss. Provides a comprehensive check on data integrity.
Disadvantages: Time-consuming and resource-intensive, especially for large datasets. Requires a reliable backup system. Can be difficult to identify the root cause of discrepancies.