A Hybrid Modified DES–Keccak Cryptographic Framework with Dynamic S-Box Design for Secure Data Confidentiality and Integrity Verification

This research presents a hybrid Modified DES–Keccak cryptographic framework that combines enhanced symmetric encryption with hash-based integrity verification in a unified architecture. The proposed method improves the conventional DES structure by introducing a 128-bit block and key mechanism, a round-dependent dynamic S-box generation approach using Keccak-256 hashing, and enhanced Feistel-based encryption operations. Unlike traditional DES variants that rely on fixed substitution tables and separate integrity mechanisms, the proposed framework integrates dynamic substitution and ciphertext authentication within a single design. The contribution of this work lies in strengthening confidentiality through improved cipher randomness and confusion while providing an additional layer of tamper detection using Keccak-256-based hash verification. The framework is experimentally evaluated in terms of computational performance, security characteristics, and integrity detection capability, demonstrating its potential as a secure alternative for modern data protection applications.