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arXiv · 2507.04501

LINE: Public-key encryption

Gennady Khalimov·Yevgen Kotukh
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Abstract

We propose a public key encryption cryptosystem based on solutions of linear equation systems with predefinition of input parameters through shared secret computation for factorizable substitutions. The existence of multiple equivalent solutions for an underdetermined system of linear equations determines the impossibility of its resolution by a cryptanalyst in polynomial time. The completion of input parameters of the equation system is implemented through secret homomorphic matrix transformation for substitutions factorized over the basis of a vector space of dimension m over the field F2. Encryption is implemented through computation of substitutions that are one-way functions on an elementary abelian 2-group of order 2"m. Decryption is implemented through completion of input parameters of the equation system. Homomorphic transformations are constructed based on matrix computations. Matrix computations enable the implementation of high security and low computational overhead for homomorphic transformations.

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Gennady Khalimov, Yevgen Kotukh. 2025-07-10. LINE: Public-key encryption. https://arxiv.org/abs/2507.04501

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