CISSP Training Kit

Hashing algorithm/message digest

Hashing algorithms, also called message digests, are primarily used for the verification of the integrity of information at the time of use of the information. The hashing algorithm is applied to the message to produce a hash value. The hash value acts as a fingerprint of the message and is initially calculated at the time of creation of a message or at other times when the information in the message is known to be complete and accurate. Then at a later time or place, when the information in the message is about to be used, the calculation is performed again and compared to the original hash value. If the two values are identical, it is concluded that the message says exactly what it did at the time it was known ...