The improvement of homophonic encryption using the well-known Z408 cipher as an example has been examined in this article. Their problems to further correct the main shortcomings of this type of encryption have been analyzed. In the practical part, an encryption system similar to Z408 has been created and the complexity of the language analysis for this cipher has been increased. The correlation data of the number of alternative characters has been used to improve the transmission of encrypted data depending on the load of the device. The more symbols and the higher the load, the fewer the number of alternative symbols will be used.
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- Elonka Dunin, Klaus Schmeh, “Code Breaking and Cryptograms”, A Practical Guide, Robinson, 2020, ISBN 978-1-472-14421-8.
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- Smart, Nigel (2004). Cryptography: An introduction ISBN 0-07-709987-7. Similar in intent to Applied Cryptography but less comprehensive.
- Patterson, Wayne (1987). Mathematical Cryptology for Computer Scientists and Mathematicians, Rowman & Littlefield, ISBN 0-8476-7438-X
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https://doi.org/10.1201/9781420010756 - Falconer, John (1685). Cryptomenysis Patefacta, or Art of Secret Information Disclosed Without a Key. One of the earliest English texts on cryptography.
- Aumasson, Jean-Philippe (2017), Serious Cryptography: A Practical Introduction to Modern Encryption. No Starch Press, 2017.
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