Kontrollsummenverifikation

Kontrollsummen, also known as checksums, are small pieces of data derived from a larger block of digital data. Their primary purpose is to detect accidental errors that may have been introduced during data transmission or storage. A control sum is calculated from the original data using a specific algorithm. When the data is received or read, the same algorithm is applied to the data again to generate a new control sum. This newly calculated control sum is then compared to the original control sum that was transmitted or stored with the data. If the two control sums match, it is highly probable that the data has remained unchanged and is error-free. If they differ, it indicates that an error has occurred somewhere in the data.

There are various types of control sum algorithms, each offering different levels of error detection capabilities and computational complexity. Simple algorithms might just sum up all the bytes in the data. More sophisticated algorithms, like Cyclic Redundancy Checks (CRCs), employ polynomial division to generate more robust checks capable of detecting a wider range of errors, including bursts of errors. Checksums are widely used in networking protocols, file transfer systems, and data integrity checks to ensure the reliability of digital information. They do not correct errors, but rather signal their presence, prompting further action like retransmission of the data.