Why is HAVAL not classified as an encryption algorithm?

The reasoning behind classifying HAVAL as a hashing algorithm rather than an encryption algorithm hinges on its intended functionality. HAVAL is specifically designed to produce a fixed-size hash value from variable-size input data. The primary purpose of hashing is to ensure data integrity by creating a unique digest of the input, allowing verification without exposing the underlying data.

In contrast, encryption algorithms are intended to transform data into a format that is unintelligible without the corresponding decryption key, allowing for secure data transmission and confidentiality. Since HAVAL does not incorporate the use of keys or provide a mechanism for reversing the hashing process (i.e., recovering the original data), it aligns with hashing rather than encryption.

The distinction is crucial in information security practices where different mechanisms are applied depending on whether the goal is to ensure the confidentiality of data or the integrity of data. Hence, HAVAL's design for hashing makes it clear that it does not serve the purpose of an encryption algorithm.