Study of The Operational Principles of Classical Encryption Algorithms
Shirinov Sherali Ramazon o‘g‘li , Teacher of the Department of Information Technologies, National Research University “TIIAME”, Uzbekistan Ergashaliyev Muhammadaziz Azamat o‘g‘li , Student of the National Research University “TIIAME”, UzbekistanAbstract
This study examines the operational principles of classical encryption algorithms, which form the foundation of modern cryptographic systems. Classical encryption techniques, including substitution ciphers, transposition ciphers, and symmetric key algorithms, are analyzed in terms of their structure, functionality, and security properties. The research focuses on understanding how plaintext is transformed into ciphertext through systematic encryption procedures and how decryption restores the original information. Special attention is given to the historical development of classical cryptography and its role in the evolution of information security. The study also evaluates the strengths and limitations of classical algorithms, particularly their vulnerability to frequency analysis and brute-force attacks. By comparing different encryption methods, the paper highlights the importance of algorithmic design in ensuring data confidentiality and integrity. The findings demonstrate that while classical encryption algorithms are relatively simple, they provide essential conceptual foundations for modern cryptographic approaches and continue to be valuable for educational and introductory purposes in cybersecurity.
Keywords
Classical encryption, cryptography, substitution cipher
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Engineering and Technology
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