A Sc–cnn-Based Chaotic Masking System With Feedback

Abstract

A secure transmission application of the State Controlled Cellular Neural Network (SC–CNN)-based circuit is presented. Since the SC–CNN-based circuit has feedback connections between the cells, it is potentially very suitable for realizing a chaotic masking system with feedback algorithm. So, we have constructed a chaotic masking system with feedback using the SC–CNN-based circuit. PSpice simulation experiments verify that the proposed SC–CNN-based secure communication system exhibits a good performance for a wide range of amplitude and spectral characteristics of the information signal.

Breaking a Sc-CNN-Based Chaotic Masking Secure Communication System

“…Recently, Kiliç et al [2004] proposed a new chaotic cryptosystem by implementing Chua's circuit with the above SC-CNN technique. It was a chaotic masking system with feedback algorithm.…”

“…This structure was originally proposed by Milanović & Zaghloul [1996] in order to obtain a robust synchronization between the transmitter and receiver of a communication scheme using a modified Lorenz chaotic system. The results of a PSpice simulation were presented by Kiliç et al [2004] and a hardware implementation was later described in [Günay & Alçi, 2005]. The cryptosystem's transmitter was defined as (also in dimensionless form):…”

“…According to the full circuit scheme of the SC-CNN-based chaotic masking system shown in Fig. 6 of [Kiliç et al, 2004], the time-scale factor is t/τ = R 24 C 21 , where t denotes the time associated with the real circuit implementation. In one of the PSpice experiments simulated in [Kiliç et al, 2004], the values of the resistor R 24 = 100KΩ and the capacitor C 21 = 51nF, which leads to a time-scale factor t/τ = R 24 C 21 = 51 × 10 −6 (or τ /t = 10 6 /51 ≈ 19608).…”

“…6 of [Kiliç et al, 2004], the time-scale factor is t/τ = R 24 C 21 , where t denotes the time associated with the real circuit implementation. In one of the PSpice experiments simulated in [Kiliç et al, 2004], the values of the resistor R 24 = 100KΩ and the capacitor C 21 = 51nF, which leads to a time-scale factor t/τ = R 24 C 21 = 51 × 10 −6 (or τ /t = 10 6 /51 ≈ 19608). This configuration was also used in the hardware realization in [Günay & Alçi, 2005] and was in fact the configuration used for all our experiments.…”

“…1. Figure 1: Waveforms from the example used in [Kiliç et al, 2004] and [Günay & Alçi, 2005]: (a) Variable x 1 (t) of the transmitter; (b) plaintext s(t) = sin(2 π 1000 t); (c) ciphertext m(t) = x 1 (t) + s(t); (d) retrieved plaintext at the receiver end s (t). Figure 2 shows the double scroll Chua's attractor resultant from the projection in the phase space of a trajectory portion extending along 0.2 s on the (x 2 , x 1 ) plane.…”