Abstract: A plaintext message to be encrypted is segmented into a number of words, e.g., four words stored in registers A, B, C and D, and an integer multiplication function is applied to a subset of the words, e.g., to the two words in registers B and D. The use of such an integer multiplication greatly increases the diffusion achieved per round of encryption, allowing for higher security per round, and increased throughput. The integer multiplication function may be a quadratic function of the form ƒ(x)=x(ax+b), where a is an even integer and b is an odd integer, or other suitable function such as a higher-order polynomial. The results of the integer multiplication function are rotated by 1 g w bits, where 1 g denotes log base 2 and w is the number of bits in a given word, to generate a pair of intermediate results t and u. An exclusive-or of another word, e.g., the word in register A, and one of the intermediate results, e.g., t, is rotated by an amount determined by the other intermediate result u.

Abstract: A plaintext message to be encrypted is segmented into a number of words, e.g., four words stored in registers A, B, C and D, and an integer multiplication function is applied to a subset of the words, e.g., to the two words in registers B and D. The integer multiplication function may be a quadratic function of the form ƒ(x)=x(ax+b) or other suitable function such as a higher-order polynomial. The results of the integer multiplication function are rotated by lg w bits, where lg denotes log base 2 and w is the number of bits in a given word, to generate a pair of intermediate results t and u. An exclusive-or of another word, e.g., the word in register A, and one of the intermediate results, e.g., t, is rotated by an amount determined by the other intermediate result u. Similarly, an exclusive-or of the remaining word in register D and the intermediate result u is rotated by an amount determined by the other intermediate result t.