Esam A. A. Hagras

Energy efficient key management scheme based on elliptic curve signcryption for Wireless Sensor Networks

In this paper, an efficient key management scheme based on public key elliptic curves signcryption (ECS) scheme for Wireless Sensor Networks (WSN) has been proposed. The proposed algorithm is compared with the scheme given in [1]. For 250 cluster node, the saving in the total number of operations, key storage requirements, energy consumptions, and communication overhead are 75%, 96%, 23.79 m Joule, and 40% respectively compared with [1]. The proposed protocol is efficient in terms of complexity, number of message exchange, computation, and storage requirements compared with [1]. The proposed key management possesses not only provided confidentiality, authentication, integrity but also unforgeability.

A New Secure Hash Dynamic Structure Algorithm (SHDSA) for Public Key Digital Signature Schemes

This paper presents a new secure hash algorithm based on dynamic structure algorithm called secure hash dynamic structure algorithm (SHDSA). It uses a famous secure hash algorithm (SHA) given by the National Institute of Standards and Technology (NIST). All NIST SHA have fixed structure, fixed constant and fixed output length. The goal of the new Advanced Encryption Standard (AES) is to offer, at its three cryptovariable size, 128, 192 and 256 bits of security, is the need for companion hash algorithms which provide similar levels of enhanced security. The basic design of SHDSA is to have variable output length of 128,192 and 256 bits, variable number of compression functions (single, double), variable number of iterations in each compression function and variable compression function structure. With this dynamic structure, it can provide many choices for practical applications with different level of security. The SHDSA has been designed to satisfy the dynamic structure algorithm with different level of enhanced security and to resist the advanced SHA attacks. The security analysis of the SFIDSA is compared to the old SHA given by the NIST and it gives more security and excellent results as shown in our discussion. In this paper, the digital signature standard algorithm (DSSA) which is given by the NIST has been modified using the proposed SHDSA. The SHDSA can be used in many applications such as, public key cryptosystems, digital signature, digital signcryption, message authentication code and random number generators

Public Key Multi-Message Signcryption (PK-MMS) Scheme For Secure Communication Systems

In this paper, a new and efficient public key multi-message signcryption (PK-MMS) scheme for provable secure communications has been proposed. The proposed scheme simultaneously signcrypts the multiple messages in a logical single step by using a multi-key generator which introduce a great deal of redundancy, efficient cost and low processing time for multi-message signcryption. The proposed PK-MMS has an efficient computation time and communication overhead compared with Zheng signcryption scheme. More specifically, it has been shown that for the minimum security parameters recommended for use in current practice, the numerical value for the saving in communication overhead using the proposed scheme are 27.7 % and 41.7 % for two and four signcrypted message over Zheng signcryption scheme. The proposed scheme costs 50 % and 75 % less in computation cost for two and four signcrypted message than does Zheng signcryption scheme.

Genetic algorithm for PAPR reduction in SLM wavelet-OFDM systems

Orthogonal frequency division multiplexing (OFDM) has lately used in wireless communication systems for its high transmission data rate and robustness against frequency selective fading. However, OFDM system suffers from a major drawback at the transmitter that is the high peak-to-average power ratio (PAPR) of the transmitted OFDM signal. Selected mapping (SLM) technique is used to achieve a good PAPR reduction without signal distortion. In this paper, an efficient PAPR reduction technique using SLM Wavelet-OFDM (WOFDM) based on Genetic Algorithm (GA) is proposed. Wavelet-OFDM (WOFDM) system has the same advantages of conventional OFDM with high PAPR reduction. GA is applied to SLM-WOFDM for searching the optimum phase rotation factors to give more reduction in PAPR. The simulation results show that the proposed system provides better PAPR reduction compared to the conventional SLM-OFDM and SLM-WOFDM systems.

C8. SLM technique based on particle swarm optimization algorithm for PAPR reduction in wavelet-OFDM systems

Orthogonal frequency division multiplexing (OFDM) system has high spectral efficiency and immunity to frequency selective fading channel. So, it has been widely used in modern wireless communication systems. However, the major drawback of OFDM system is the high peak-to-average power ratio (PAPR) of the transmitted signal for large number of subcarriers. Selected mapping (SLM) is one of the most well-known technique to reduce the PAPR in OFDM system, since it can achieve a good PAPR reduction without signal distortion. Moreover, SLM technique can be used with wavelet-OFDM (WOFDM) system to enhance the PAPR performance, while maintaining most of the advantages of the conventional OFDM system. In this paper, an effective PAPR reduction technique using SLM-WOFDM based on particle swarm optimization (PSO) algorithm is proposed. PSO is applied to SLM-OFDM and SLM-WOFDM systems for searching the optimum phase rotation factors. The systems evaluation shows that the proposed PSO based SLM-WOFDM system provides better PAPR reduction compared to PSO based SLM-OFDM, SLM-WOFDM, and conventional SLM-OFDM systems.

A new efficient public key multi-message multi-recipient signcryption (PK-MM-MRS) scheme for provable secure communications

In this paper, a new efficient public key multi-messages multi-recipients signcryption (PK-MM-MRS) scheme for provable secure communications has been proposed. The proposed scheme signcrypted multiple messages for each recipient using a multi-key generator. The multi-key generator played an important role for the communication overhead and computational cost saving in the proposed PK-MM-MRS scheme. This scheme has an efficient communication overhead and computational cost saving compared to Zheng multi-recipient signcryption scheme. The numerical values for the saving in communication overhead using the proposed scheme are 38.24% for two messages, two recipients and 67.97% for three messages ,three recipients than does Zheng multi-recipient signcryption scheme with same parameters. The proposed scheme costs 50% and 75% less in computation cost for two and four signcrypted messages over Zheng multi-recipient signcryption scheme. The saving in communication overhead and computational cost is increased as the number of messages and recipients increases.

Robust Blind and Secure Biometric Watermarking Based on Partial Multi-Map Chaotic Encryption

In this paper, a novel Commutative Watermarking and Partial Encryption (CWPE) algorithm using single level 2-Dimension Discrete Wavelet Transform (CWPE 2D DWT) and Multi-Map Orbit Hopping Chaotic System (MMOH-CS) is proposed. The experimental results show that the proposed algorithm is robust against common signal processing attacks such as Salt & Pepper noise, Gaussian noise, Wiener filter, JPEG compression, Resizing and Cropping. The proposed scheme is able to reduce encryption to one quarter of the image information. Statistical analysis, differential analysis and key sensitivity test are performed to estimate the security strength of the proposed algorithm. The results of the security analysis show that the proposed algorithm provides a high security level for real time application.

PAPR reduction for downlink LTE system based on DCT and Hyperbolic Tangent Companding noise cancellation

A joint Hyperbolic Tangent Companding (HTC) technique and Discrete Cosine Transform (DCT) has been proposed to decrease of the PAPR ratio effects of the OFDMA System. The proposed schema utilizes DCT instead of the traditional discrete Fourier transform (DFT) as a requisite function to perform DCT OFDMA. HTC is an actual process to minimize the high PAPR of DCT OFDMA. However, the companded DCT OFDMA suffers from the bit-error-rate (BER) performance degradation by companding noise introduced. So, an effective scheme of estimation and noise cancellation for the compressed DCT OFDMA is introduced. By expressing the compressed signals as a combination of the main signals adding with the component of compressed noise, and the estimated compressed noise deduct from the received signals, leading to enhance the BER performance of the proposed system. The new proposed scheme minimizes PAPR by about 6.3 dB and 7.3 dB compare respectively, with the DFT OFDMA and DCT OFDMA without commanding. Also, it is noted that the proposed scheme of estimation and companding noise cancellation for the companded DCT OFDMA provides a great lowest BER degradation that can be neglected comparing with the premier DCT SC-FDMA system without PAPR reduction.

Genetic algorithm based tone-reservation for PAPR reduction in wavelet-OFDM systems

High peak-to-average power ratio (PAPR) is one of the main problems that faces the orthogonal frequency division multiplexing (OFDM) system. Tone reservation (TR) technique is used to reduce this problem without introducing any new distortion. Moreover, TR technique can be used with wavelet-OFDM (WOFDM) system to enhance the PAPR performance, while maintaining most of the advantages of the OFDM system. A TR-WOFDM system that employed genetic algorithm (GA) is proposed in this paper to achieve a high PAPR reduction performance. GA is introduced to TR-WOFDM system to search the optimal positions of reserved tones. A comparative study is done to evaluate the proposed GA-TR-WOFDM system compared to GA-TR-OFDM, TR-WOFDM, and TR-OFDM systems in the sense of CCDF. The systems evaluation shows that the proposed technique outperforms the other studied techniques in achieving better PAPR reduction.

C4. Multi Rate Single Code Multi Carrier Superposition Coded Modulation (MR-SC-MC-SCM) for Multi User Communications

This paper introduces a Multi Rate Single Code Multi Carrier Superposition Coded Modulation (MR-SC-MC-SCM) for Multi User Communication System, achieving Un-equal Error Protection (UEP) for each user using the multi rate coding concept to provide different levels of data protection based on the user application requirement with some complexity reduction. Saleh model is used as a High Power Amplifier (HPA) and the system performance has been studied over Additive White Gaussian Noise (AWGN), fading channel Jack model and Rician channel. A simple Chip-By-Chip (CBC) iterative Multi User Detection (MUD) strategy is used. The main contribution of this paper is to reduce the transceiver complexity in terms of number of encoders and decoders with minor performance degradation in-terms of Bit Error Rate (BER).