What is the main purpose of file hashing?

Data integrity verification is a crucial aspect of ensuring the reliability and authenticity of digital information. In the realm of data transmission and storage, it becomes even more imperative to guarantee that the data remains unchanged and free from any unauthorized alterations.

One of the most effective methods for accomplishing this is through file hashing. Hashing is a cryptographic process that converts data of any size into a fixed-length string of characters, known as a hash value. This hash value serves as a unique digital fingerprint for the data.

The process of verifying data integrity involves calculating the hash value of a file before it is transmitted or stored. This initial hash value serves as a reference point, allowing for a later comparison to determine if the file has remained unchanged.

After the transmission or storage process is complete, the hash value of the file is recalculated. This second hash value is then compared to the initial hash value. If the two hash values match, it indicates that the file has remained intact and has not been modified or corrupted.

However, if the hash values do not match, it signals that the file has undergone some form of alteration. This could be due to accidental corruption during transmission or storage, or more concerningly, it could indicate malicious tampering.