A Wrapping Encryption Based on Double Randomness Mechanism

Abstract

Currently, data security mainly relies on password (PW) or system channel key (SK_CH) to encrypt data before they are sent, no matter whether in broadband networks, the 5th generation (5G) mobile communications, satellite communications, and so on. In these environments, a fixed password or channel key (e.g., PW/SK_CH) is often adopted to encrypt different data, resulting in security risks since this PW/SK_CH may be solved after hackers collect a huge amount of encrypted data. Actually, the most popularly used security mechanism Advanced Encryption Standard (AES) has its own problems, e.g., several rounds have been solved. On the other hand, if data protected by the same PW/SK_CH at different time points can derive different data encryption parameters, the system’s security level will be then greatly enhanced. Therefore, in this study, a security scheme, named Wrapping Encryption Based on Double Randomness Mechanism (WEBDR), is proposed by integrating a password key (or a system channel key) and an Initialization Vector (IV) to generate an Initial Encryption Key (IEK). Also, an Accumulated Shifting Substitution (ASS) function and a three-dimensional encryption method are adopted to produce a set of keys. Two randomness encryption mechanisms are developed. The first generates system sub-keys and calculates the length of the first pseudo-random numbers by employing IEK for providing subsequent encryption/decryption. The second produces a random encryption key and a sequence of internal feedback codes and computes the length of the second pseudo-random numbers for encrypting delivered messages. A wrapped mechanism is further utilized to pack a ciphertext file so that a wrapped ciphertext file, rather than the ciphertext, will be produced and then transmitted to its destination. The findings are as follows. Our theoretic analyses and simulations demonstrate that the security of the WEBDR in cloud communication has achieved its practical security. Also, AES requires 176 times exclusive OR (XOR) operations for both encryption and decryption, while the WEBDR consumes only 3 operations. That is why the WEBDR is 6.7~7.09 times faster than the AES, thus more suitable for replacing the AES to protect data transmitted between a cloud system and its users.