Implementation of Layered Encryption Using Vigenère and Rail Fence Cipher on Live Chat Systems for Customer Data Security

Abstract

The security of digital communication has become increasingly crucial with the growing use of instant messaging services. This study aims to design and implement a live chat system that applies layered encryption using two classical cryptographic algorithms, namely Vigenère Cipher and Rail Fence Cipher, to enhance message confidentiality. Messages sent by users are first encrypted using the ASCII-based Vigenère Cipher with mod 256, and then encrypted again using the Rail Fence Cipher with a zigzag pattern. The testing process considered several parameters such as message length (10–100 characters), variations in key length, number of rails (2–5), and the number of messages sent per minute. The results indicate that the combination of these two algorithms can maintain message security without affecting real-time communication performance. This approach demonstrates that layered encryption using classical algorithms is still relevant for enhancing the security of digital communications in small to medium-scale applications.