Patent ID: 7961876
Filing Date: 2011-06-14
Classification: H04L

Abstract:
1. A cryptographic method for application to a multivariate public key cryptosystem (MPKC) to produce new multivariate public key cryptosystems or asymmetric cryptographic communication processes, wherein said multivariate public key cryptosystem is a cryptographic communication process comprising: a) a public transformation which transforms a value (X) represented by a vector of k b) a secret transformation for obtaining the value (X) from the value (Y) by means of inverting the transformation defined by (f c) wherein producing a family of new multivariate public key cryptosystems or new asymmetric cryptographic communication process over any prior existing MPKC, which refers to any existing or future MPKC that does not use the method in its design, comprising the steps: i) adding directly into the prior MPKC internal perturbation through a small number (r) of randomly or specially chosen new internal variables  i=1, . . . , r whose linear part without the constant term b ii) appending (α) more components, which are randomly or specially chosen polynomials to the already perturbed MPKC, and composing randomly or specially chosen invertible affine or linear transformations, such that a newly produced MPKC improved by the method, has a new public transformation for transforming the value (X) represented by (n) elements of a finite field, or ring (k), X=(x iii) a secret transformation for obtaining the value (X) from the value (Y