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@article{171189,
        author = {Saketh N Shet and Chakrapani D S and Sathwik SM and Shashank HN and Sanjay PS},
        title = {Hybrid Cryptosystem using Modified Polybius and Vigenere Cipher for File Encoding in GIF},
        journal = {International Journal of Innovative Research in Technology},
        year = {2024},
        volume = {11},
        number = {7},
        pages = {3712-3717},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=171189},
        abstract = {In the era of rapid digital transformation, securing sensitive information from unauthorized access has become a critical challenge. Cryptographic techniques play a vital role in protecting data against potential cyber threats. This research presents a Hybrid Cryptosystem that combines the strengths of two classical encryption methods—the Vigenère cipher and the Polybius cipher—to create a robust, dual-layered encryption framework. The system employs unique dual keys for each cipher, supporting extended ASCII characters to ensure compatibility with modern data formats. The hybrid approach enhances cryptographic strength by combining polyalphabetic substitution and coordinate-based transposition, making it resilient against common cryptanalysis techniques like frequency analysis and brute force attacks. The research contributes to advancing cryptographic techniques by showcasing the innovative integration of classical encryption methods with modern technology.},
        keywords = {Polybius, Vigenère, cryptosystem, encryption, decryption},
        month = {December},
        }