Basic Cryptography: Implementing Caesar Cipher Encryption and Decryption in MATLAB

Abstract

This study is an emphasis on the implementation of MATLAB and analysis of the Caesar Cipher encryption and decryption processes with exhaustive coverage of the ancient cryptographic algorithm. The process involves the coding of both the Caesar Cipher encryption process and the decryption process in which the key is utilized as a shift parameter in letter conversion during the plaintext. The study looks at the impact of different shift keys on the output ciphertext and the vulnerability of the cipher to brute-force attack by brute-forcing all feasible shifts. The findings show that while the Caesar Cipher offers a basic introduction to cryptography, it is extremely vulnerable to brute-force decryption because it has such a tiny key space (only 25 possible shifts). By a series of test cases, it was demonstrated that the shift key significantly alters the ciphertext, but since there is a limited number of possible keys, decryption is relatively simple. This discussion points out the necessity of employing more advanced algorithms in modern cryptography to ensure data protection, as evident from the juxtaposition of the ease of the Caesar Cipher with the complexity of modern encryption algorithms like AES and RSA. The study further stresses the significance of key management while encrypting information. The implication of this study is that there is a requirement for continuous evolution in cryptographic techniques, especially with the emergence of new technologies such as quantum computing. The Caesar Cipher can be of historical interest, but it is mostly employed as an educational tool in the study of elementary cryptographic principles.