Abstract: A multiple-input multiple-output s-box receives a contiguously numbered input bits (101, 102, 103, 104, 105) I1, I2 to Ia, where a is at least 4, and outputs b contiguously numbered output bits (131, 132, 133, 134, 135) O1, O2, to Ob. The s-box comprises c primitive s-boxes (121, 122, 123) sb1 sb2 to sbc. Each primitive s-box (121, 122, 123) has a multiple-input single-output Boolean function ƒ1, ƒ2, to ƒo defining the relationship between the multiple inputs and the single output. Each primitive s-box (121, 122, 123) receives a set of input bits s1, s2, to sc, respectively, each such set is chosen from the a input bits (101, 102, 103, 104, 105) to the s-box and containing sl1, sl2, to slc bits respectively. Each of the numbers sl1, sl2, to slc, is in the range of 3 to (a?1), and the sum of the numbers sl1, sl2, to slc is larger than a. The b output bits of the s-box (131, 132, 133, 134, 135) are the outputs of the c Boolean functions.

Abstract: A process (100, 200, 300) receives at least one block of plaintext material (161, 163, 271, 273) and initializes intermediate text (150, 250). The intermediate text (150, 250) is larger than 58 octets. An updating process includes the invocation of at least one round function (171, 172, 282, 282). Each round function (171, 172, 282, 282) receives inputs which are one input selected from the intermediate text (150, 250), at least two inputs selected from the intermediate text (150, 250), so that each pair of the at least two inputs selected from the intermediate text (150, 250) is separated by at least one bit of intermediate text (150, 250). Each of the inputs is at least 2 bits in length. Each round function (171, 172, 282, 282) generates at least one output that updates at least two bits of the intermediate text (150, 250).

Abstract: A cryptographic process includes an initialization process, invokes at least one round function (171, 172, 281, 282) and has an output function. The initialization process initializes intermediate text (150, 250) which has more than 58 octets. Each round function (171, 172, 281, 282) updates the intermediate text. Each round function (171, 172, 281, 282) has one input selected from the intermediate text (150, 250), at least two inputs selected from the intermediate text (150, 250), so that each pair of the at least two inputs selected from the intermediate text (150, 250) is separated by at least one bit of intermediate text (150, 250). Each of the inputs is at least two bits in length. The sum of the length of the inputs received by the round function (171, 172, 281, 282) from the intermediate text (150, 250) is less than the length of the intermediate text (150, 250) in bits minus six times the length of the sum of the output bits of the round function (171, 172, 281, 282).

Abstract: A cryptographic process (100) receives variable length user data (150) as input and performs an initialization process, at least one pass of at least one pass function and an output function. The pass function the invokes at least one round function (171). Each round function (171) receives inputs which are at least one reversible input (151) selected from the intermediate text (150), at least two irreversible inputs (152, 157) selected from the intermediate text (150), so that each pair of the at least two irreversible inputs (152, 157) are selected from the intermediate text (150) so that they separated by at least one bit of intermediate text (150). The round function (171) generates at least one reversible output (151) that updates the intermediate text (150).