Earticle

Wireless sensor networks (WSNs) are a technology of various uses from monitoring surrounding environment to collecting data. Because WSNs operate with limited resources of sensor nodes, its life is extended by cluster-based routing methods. However, WSNs which communicate through a wireless transmission medium are quite vulnerable in terms of security compared to wired networks and their sensor nodes have very limited communication and computing capacities and a small memory space. For these reasons, it is difficult to apply the established public key encryption technology. Accordingly, a large number of sensor nodes should be tolerable to errors and failures, and it is essential to achieve effective management and reinforced security functions through autonomous network construction. The cluster-based routing protocol proposed in this study showed energy-efficient key management by establishing a common shared key through the key of key ring or through authentication by a reliable institution.

Recently, most of malicious web pages include obfuscated codes in order to circumvent the detection of signature-based detection systems .It is difficult to decide whether the sting is obfuscated because the shape of obfuscated strings are changed continuously. In this paper, we propose a novel methodology that can detect obfuscated strings in the malicious web pages. We extracted three metrics as rules for detecting obfuscated strings by analyzing patterns of normal and malicious JavaScript codes. They are N-gram, Entropy, and Word Size. N-gram checks how many each byte code is used in strings. Entropy checks distributed of used byte codes. Word size checks whether there is used very long string. Based on the metrics, we implemented a practical tool for our methodology and evaluated it using read malicious web pages. The experiment results showed that our methodology can detect obfuscated strings in web pages effectively.

Superiority of poly-alphabetic sequences (PAS) for pulse compression radar over the binary and ternary sequences was established earlier. However, the enlarged alphabets in poly–alphabetic sequences deteriorate the noise and Doppler robustness at higher lengths in high resolution radar (HRR) systems. In this paper, poly-semantic sequences (PSS) with restricted alphabet {+1,-1} are considered and their performance is analyzed in order to achieve superior detection performance for high resolution radar system in presence of high density additive noise and Doppler shift. The poly-semantic sequences are optimized by employing modified Hamming scan algorithm called Hamming backtrack algorithm (HBT) by taking figure of merit as the measure of goodness. The detection capability of poly-semantic sequences is further improved through coincidence detection of the return signal. The simulation results show that the proposed sequences give improved robustness of noise and Doppler shift for HRR target detection compared to conventional pulse compression sequences.

As a public key cryptography, Elliptic Curve Cryptography (ECC) is well known to be the most secure algorithms that can be used to protect information during the transmission. ECC in its arithmetic computations suffers from modular inversion operation. Modular Inversion is a main arithmetic and very long-time operation that performed by the ECC crypto-processor. The use of projective coordinates to define the Elliptic Curves (EC) instead of affine coordinates replaced the inversion operations by several multiplication operations. Many types of projective coordinates have been proposed for the elliptic curve E: y2 =x3 +ax+b which is defined over a Galois field GF(p) to do EC arithmetic operations where it was found that these several multiplications can be implemented in some parallel fashion to obtain higher performance. In this work, we will study Hessian projective coordinates systems over GF (p) to perform ECC doubling operation by using parallel multipliers to obtain maximum parallelism to achieve maximum gain.

It is apprehended that the human element of trust is becoming the number one asset for the financial organisations. And since trust is a matter of relationships, financial organisations need to create, expand and maintain consumer trust for communication, transactions and payments. Financial institutions are known for their ability to cultivate long-standing relationships with their clients based on integrity and trust. And as we move towards electronic-based transactions, there is the need to explore the factor of trust in order to identify how financial organizations are shaped in the future and what issues are raised. Trust always affects two measurable outcomes: speed and cost and there are essentially two mechanisms that lead to economic notions of trust, the one is based on repeated interaction the other one is based on beliefs. The ultimate goal is to engage online commerce users quickly and establish and preserve strategic trust under challenging situations. In the ecommerce context, based on the target, the study of trust can be categorized as macro-level or micro-level. The macro-level study of trust deals with what called institution-based trust and the micro-level study of trust is different from the macro-level study in that the target of the former is an individual e-business. The research questions that are brought in the surface are: what exactly is trust in the on-line environment? What are the sources of trust? Is there more than one form of trust? Is it a static or dynamic phenomenon etc. The paper will try to explore, examine, and describe the methods for estimating the economic value of trust (cost of developing trust, maintaining trust and trust failure), the impacts of trust on e –-economy (general finding) and how trustworthy financial organizations are created and finally financial organizations benefit from trust.

Visual cryptography scheme is a cryptographic technique which allows visual information (e.g. printed text, handwritten notes, and picture) to be encrypted in such a way that the decryption can be performed by the human visual system, without the aid of computers. There are various measures on which performance of visual cryptography scheme depends, such as pixel expansion, contrast, security, accuracy, computational complexity, share generated is meaningful or meaningless, type of secret images( either binary or color) and number of secret images(either single or multiple) encrypted by the scheme. Intent of this paper is on study and performance analysis of the visual cryptography schemes on the basis of pixel expansion, number of secret images, image format and type of shares generated.