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arXiv · 1909.06781

A Vector Space Approach to Generate Dynamic Keys for Hill Cipher

Sunil Kumar·Sandeep Kumar·Gaurav Mittal·Shiv Narain
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Abstract

In this paper, a variant of the Hill cipher is proposed. In the classical Hill cipher, an invertible matrix is used for encryption but the scheme is vulnerable to the known-plaintext attack which can reveal the matrix. In our proposed cryptosystem, each plaintext block is encrypted by a new invertible key matrix that thwarts the known-plaintext attack. To generate the invertible matrices which serve as the dynamic keys we make use of the vector spaces, randomly generated basis and non-singular linear transformation. Resulting cipher is secure against the known-plaintext attack.

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Sunil Kumar, Sandeep Kumar, Gaurav Mittal, Shiv Narain. 2019-09-15. A Vector Space Approach to Generate Dynamic Keys for Hill Cipher. https://arxiv.org/abs/1909.06781

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