Finite-field audio encryption based on nonlinear modular recurrence and recursive diffusion

doi:10.1007/s11042-026-21931-1

Finite-field audio encryption based on nonlinear modular recurrence and recursive diffusion

2026-09-19

0

PRE

AI

DOI：10.1007/s11042-026-21931-1

Original

Original request for help

Save

Abstract

En 中文

This paper presents a finite-field audio encryption framework based on a nonce-dependent nonlinear recurrence, nonlinear finite-field transformation, multiplicative scrambling, and recursive and global diffusion. Input audio samples are mapped to the prime finite field, and the encryption operations are performed using modular arithmetic. A second-order nonlinear recurrence generates a session-dependent keystream, which is combined with a two-round nonlinear pairwise transformation, multiplicative scrambling, forward and backward nonlinear diffusion, and two invertible global diffusion stages. The resulting construction has an explicitly defined algebraic inverse, providing exact recovery of the quantized finite-field representation; reconstruction of the original real-valued audio remains subject to the quantization introduced during the audio-to-field mapping. For $$q=65537$$ , the nominal parameter-combination space defined by the six secret recurrence parameters and the multiplicative parameter is $$|\mathcal {K}|=q^{6}(q-1)\approx 2^{112}$$ ; this value represents the nominal parameter space and is not interpreted as an established effective cryptographic key strength. Experimental evaluation on publicly available audio signals demonstrates exact finite-field reconstruction, high-fidelity real-valued reconstruction, favorable ciphertext statistical characteristics, and strong differential propagation for the complete configuration. Sensitivity experiments show that small perturbations of the recurrence parameters produce substantial changes in the generated keystream, while ablation experiments indicate that recursive and global diffusion make major contributions to perturbation propagation. The encryption and decryption procedures have linear asymptotic complexity, O(N), and their execution time, throughput, working-memory requirement, and scalability are experimentally characterized. The results provide a reproducible finite-field framework for quantized audio encryption and an empirical evaluation of its reconstruction fidelity, diffusion behavior, recurrence sensitivity, and computational performance.

Keywords:

Finite-field audio encryption

Nonlinear recurrence keystream

modular arithmetic

multimedia security

Finite-field audio encryption based on nonlinear modular recurrence and recursive diffusion

Abstract

Journal

Organization

Cited Papers