Question

The registers ‘a’ and ‘e’ involve

(a) Permutation and substitution both

(b) Only Permutation

(c) Only substitution

(d) Don’t undergo any operations

The question was asked at a job interview.

The above asked question is from Secure Hash Algorithms (SHA) in section Other Public Key Cryptosystems and Cryptographic Hash Functions of Cryptograph & Network Security

Answer 1

The correct option is (c) Only substitution

The explanation is: The registers ‘a’ and ‘e’ undergo substitution and not permutation.