Binary Sequence Generated by Alternative Trace Map Function and Its Properties In this paper, we propose a new pseudo random binary sequence generated from a primitive polynomial over an extension field. The sequence has maximum period and high linear complexity suitable for security applications. While generation, a new mapping function is proposed which is faster than conventional trace map and translates extension field elements to prime field elements. The output of mapping function is a pary sequence with elements 0 (p1) that is balanced in pattern distribution and has ideal autocorrelation. Then, a binarization method is utilized to derive binary sequence from pary sequence. Period, autocorrelation, linear complexity and computation time of the proposed sequence are studied and experimental results are presented. Finally, the efficiency of the proposal is verified by comparing with existing sequences in terms of period, linear complexity and generation time for sequences of different length.

An Efficient Cryptosystem based on the LogisticChebyshev Map We utilise the LogisticChebyshev map as a cascade discretetime chaotic system to design a new form of a cryptosystem. Based on the LogisticChebyshev map, we present a novel method for constructing substitution boxes or Sboxes. The performance of the proposed Sbox scheme is investigated. Our results shows that the constructed Sbox has significant qualities for viable applications in security related domains. Additionally, we utilise a new pseudorandom number generator (PRNG) scheme for the purpose of generating keystreams for further encryption. We utilise this technique to demonstrate how a PRNG based chaotic system can be utilsied for image encryption. Our simulation results and analysis show that the proposed scheme has efficient performance for cryptographic based image processing applications.