Security and Performance Analysis of the Caesar Cipher Algorithm Against Cryptanalysis Attacks Based on Kerckhoffs Principle with Implementation Using the Python Programming Language

Abstract

This study analyzes the security of the Caesar Cipher algorithm against cryptanalysis attacks based on the Kerckhoffs Principle through an implementation in the Python programming language. The Kerckhoffs Principle states that the security of a cryptographic system should rely solely on the secrecy of the key rather than the secrecy of the algorithm. Caesar Cipher is a classical monoalphabetic substitution cipher that encrypts data by shifting each letter by a fixed number of positions in the alphabet. The objectives of this research are to implement the Caesar Cipher algorithm, evaluate its security level, and simulate a brute force cryptanalysis attack using Python. Experimental results demonstrate that the algorithm performs encryption and decryption with 100% accuracy. However, it exhibits a critical security weakness due to its extremely limited key space of only 25 possible keys. The brute force simulation successfully recovered the ciphertext in less than one second, demonstrating that the algorithm fails to satisfy modern cryptographic security requirements. Furthermore, the evaluation based on the Kerckhoffs Principle confirms that the Caesar Cipher does not provide practical security because its protection depends on a very limited key space. This research provides educational insights into the importance of selecting robust cryptographic algorithms and highlights the relevance of the Kerckhoffs Principle as a framework for evaluating cryptographic security.