US5838794A — Method and apparatus for inter-round mixing in it…

Claim 1

Independent Claim 258 words

A method of encryption to be performed by a computer, comprising the steps of: (a) receiving successive blocks of data, each block of data being sub-divided into n sub-blocks of data, where n is an integer, each sub-block being assigned to one of n substitution boxes; (b) selecting one of a quick trickle or a quasi quick trickle permutation as a base permutation; (c) determining if a set of preselected exponents is to be applied to the base permutation; (d) generating the set of preselected exponents from one of quick trickle or a quasi quick trickle permutation; (e)(1) applying the set of preselected exponents to the base permutation if step (c) determines that a set of preselected exponents is to be applied, to obtain a sequence of permutations, otherwise (e)(2) applying an exponent of one to the base permutation to obtain a resulting permutation; (f) for each round in a determined number of rounds, if step (e)(1) is applied, applying a corresponding one of the sequence of permutations to the substitution boxes, assigning an output of each numbered substitution box as an input to the substitution box whose number is indicated by the corresponding one of the sequence of permutations, and if step (e)(2)is applied, applying the resulting permutation to the substitution boxes, assigning an output of each numbered substitution box as an input to the substitution box whose number is indicated by the resulting permutation; (g) repeating steps (e) and (f) for the predetermined number of rounds; and (h) displaying the encrypted data provided in step (g).

Claim 2

Independent Claim 258 words

A method of encryption to be performed by a computer, comprising the steps of: (a) receiving successive blocks of data, each block of data being sub-divided into n sub-blocks of data, where n is an integer, each sub-block being assigned to one of n substitution boxes; (b) selecting one of a quick trickle or a quasi quick trickle permutation as a base permutation; (c) determining if a set of preselected exponents is to be applied to the base permutation; (d) generating the set of preselected exponents from one of quick trickle or a quasi quick trickle permutation; (e)(1) applying the set of preselected exponents to the base permutation if step (c) determines that a set of preselected exponents is to be applied, to obtain a sequence of permutations, otherwise (e)(2) applying an exponent of one to the base permutation to obtain a resulting permutation; (f) for each round in a determined number of rounds, if step (e)(1) is applied, applying a corresponding one of the sequence of permutations to the substitution boxes, assigning an output of each numbered substitution box as an input to the substitution box whose number is indicated by the corresponding one of the sequence of permutations, and if step (e)(2)is applied, applying the resulting permutation to the substitution boxes, assigning an output of each numbered substitution box as an input to the substitution box whose number is indicated by the resulting permutation; (g) repeating steps (e) and (f) for the predetermined number of rounds; and (h) displaying the encrypted data provided in step (g).

Claim 3

Dependent Claim 12 words

The method of claim 1, wherein in step (a), n is even.

Claim 4

Dependent Claim 42 words

The method of claim 2, wherein in step (b), the quick trickle permutation is one in which a totality of spacings from a location of an element i to a location of an element i+1 are all different and constitute a sequencing.

Claim 5

Dependent Claim 286 words

The method of claim 3, wherein step (b) comprises the step of selecting the quick trickle permutation as the base permutation and generating the base permutation by: providing a first sequencing {0,a 1 ,a 2 , . . . ,a n-1 } which is a sequence of all of the elements of a group of n elements arranged in such an order that the sequence of partial sums b 0 =0, b 1 =a 1 , b 2 =a 1+a 2 , b 3 =a 1 +a 2 +a 3 , . . . , b n-1 , are all different; wherein in step (d) the step of generating the set of preselected exponents comprises the step of: selecting and generating a second quick trickle permutation by providing a second sequencing {0,a 1 ,a 2 , . . . ,a n-n } which is a sequence of-all of the elements of a group of n elements arranged in such an order that the sequence of partial sums b 0 =0, b 1 =a 1 , b 2 =a 1 +a 2 , b 3 =a 1 +a 2 +a 3 . . . b n-1 , are all different, and wherein in step e)(1), the step of applying the set of preselected exponents comprises the step of applying successive integers of the second sequencing as the set of preselected exponents of the base permutation at the end of each round provides a sequence of permutations g 0 , g a .sbsp.1, g a .sbsp.2 . . . , g a .sbsp.n-1 in each of which a totality of spacings from a location of an element i to a location of an element i+1 are all different.

Claim 6

Dependent Claim 15 words

The method of claim 4, wherein the number of rounds is a multiple of n.

Claim 7

Dependent Claim 14 words

The method of claim 4, wherein the first and the second sequencings are identical.

Claim 8

Dependent Claim 14 words

The method of claim 4, wherein the first and the second sequencings are different.

Claim 9

Dependent Claim 323 words

The method of claim 3, wherein step (b) comprises the step of selecting the quasi-quick trickle permutation as the base permutation and generating the base permutation by; providing a quasi-sequencing which is a sequence of elements {a i } of a group of n elements (0, a 1 , a 2 , . . . , a n-1 }, where the following occurs: when there is a group element a i such that a i =a i -1 it occurs once, and for any other group element, one of the following occurs: either (i) a i occurs twice and a i -1 does not occur, or (ii) a i and a i -1 each occurs once; where the group of n elements is arranged such that the sequence of partial sums b 0 =0, b 1 =a 1 , b 2 =a 1 +a 2 , b 3 =a 1 +a 2 +a 3 . . . b n-1 , are all different; wherein step (d) comprises the step of selecting set of preselected exponents by selecting a quick trickle permutation and generating the quick trickle permutation by providing a sequencing {0,a 1 ,a 2 , . . . ,a n-1 } which is a sequence of all of the elements of a group of n elements arranged in such an order that the sequence of partial sums b 0 =0, b 1 =a 1 , b 2 =a 1 +a 2 , b 3 =a 1 +a 2 +a 3 . . . b n-1 , are all different; and wherein in step (e)(1) the step of applying the set of preselected exponents comprises the step of applying successive integers of the sequencing as the set of preselected exponents of the base permutation at the end of each round provides a sequence of quasi quick trick permutations g 0 ,g 0 ,g a .sbsp.1,g a .sbsp.2, . . . ,g a .sbsp.-1.

Claim 10

Dependent Claim 15 words

The method of claim 1, wherein the set of preselected exponents consists of one exponent.

Claim 11

Dependent Claim 175 words

The method of claim 1, wherein step (b) comprises the step of selecting the quasi quick trickle permutation as the base permutation, where the quasi quick trickle permutation is one in which the spacings i to i+1 are given by elements a i of a quasi-sequencing which is a sequence of elements {a i } of a group of n elements {0, a 1 , a 2 , . . . , a n-1 }, where the following occurs: where there is a group element a i such that a i =a i -1 , it occurs once, and for any other group element, one of the following occurs: either (i) a i occurs twice, and a i -1 does not occur, or (ii) a i and a i -1 each occurs once; where the group of n element is arranged such that the sequence of partial sums b 0 =0, b 1 =a 1 , b 2 =a 1 +a 2 . . . , b n-1 are all different and constitute a quasi-sequencing.

Claim 12

Dependent Claim 391 words

The method of claim 10, wherein step (b) comprises the step of selecting the quasi quick trickle permutation as the base permutation, and generating the base permutation by: providing a first quasi-sequencing which is a sequence of elements {a i } of a group of n elements {0,a 1 ,a 2 , . . . ,a n-1 }, where the following occurs: when there is a group element a i such that a i =a i -1 , it occurs once, and for any other group element, one of the following occurs: either (i) a i occurs twice, and all does not occur, or (ii) a i and a i - each occurs once; where the group of n elements is arranged such that the sequence of partial sums b 0 =0, b 1 =a 1 , b 2 =a 1 +a 2 , b 3 =a 1 +a 2 +a 3 . . . b n-1 , are all different; wherein in step (d) the step of generating the set of preselected exponents comprises the step of selecting a second quasi quick trickle permutation generating the second quick trickle permutation by providing a second quasi-sequencing which is a sequence of elements {a i } of a group of n elements {0,a 1 ,a 2 , . . . ,a n-1 }, where the following occurs: when there is a group element a i such that a i =a i -1 , it occurs once, and for any other group element, one of the following occurs: either (i) a i occurs twice, and a i -1 does not occur, or (ii) a i and a i -1 each occurs once; where the group of n elements is arranged such that the sequence of partial sums b 0 =0, b 1 =a 1 , b 2 =a 1 +a 2 , b 3 =a 1 +a 2 +a 3 . . . b n-1 , are all different; and wherein in step (e)(1) the step of applying the set of preselected exponents comprises the step of applying successive integers of the second quasi-sequencing as the set of preselected exponents of the base permutation at the end of each round provides a sequence of quasi quick trickle permutations g 0 ,g 0 ,g a .sbsp.1,g a .sbsp.2, . . . ,g a .sbsp.-1.

Claim 13

Dependent Claim 15 words

The method of claim 11, wherein the first and the second quasi sequencings are identical.

Claim 14

Dependent Claim 15 words

The method of claim 11, wherein the first and the second quasi sequences are different.

Claim 15

Dependent Claim 335 words

The method of claim 1, wherein step (b) comprises the step of selecting the quick trickle permutation as the base permutation and generating the base permutation by: providing a sequencing (0,a 1 , a 2 , a n-1 which is a sequence of all of the elements of a group of n elements arranged in such an order that the sequence of partial sums b 0 =0, b 1 =a 1 , b 2 =a 1 +a 2 , b 3 =a 1 +a 2 +a 3 . . . b n-1 , are all different; wherein in step (d) the step of generating the set of preselected exponents comprises the step of: selecting and generating a quasi quick trickle permutation by providing a quasi-sequencing which is a sequence of elements {a i } of a group of n elements {0,a 1 ,a 2 , . . . ,a n-1 }, where the following occurs: when there is a group element a i such that a i =a i -1 , it occurs once, and for any other group element, one of the following occurs: either (i) a i occurs twice and a i -1 does not occur, or (ii) a i and a i -1 each occurs once; where the group of n elements is arranged such that the sequence of partial sums b 0 =0, b 1 =a 1 , b 2 =a 1 +a 2 . . . , b n-1 , are all different; and wherein in step (e)(1) the step of applying the set of preselected exponents comprises the step of applying successive integers of the quasi-sequencing as the set of preselected exponents of the base permutation at the end of each round provides a sequence of quick trickle permutations g 0 ,g 0 ,g a .sbsp.1,g a .sbsp.2, . . . ,g a .sbsp.-1 in each of which a totality of spacings from a location of an element i to a location of an element i+1 are all different.

Claim 16

Dependent Claim 15 words

The method of claim 14, wherein the number of rounds is a multiple of n.

Claim 17

Dependent Claim 12 words

The method of claim 1, wherein in step (a), n is odd.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2001-11-16	2002-05-18	2002-11-17	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2005-11-16	2006-05-18	2006-11-17	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2009-11-16	2010-05-18	2010-11-17	$7700.00	Window Closed / Lapsed

Method and apparatus for inter-round mixing in iterated block substitution systems

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