ID-based constant-round group key agreement protocols are efficient in both computation and communication, but previous protocols did not provide valid message authentication. An improvement based on attack analysis is proposed in this paper. The improved method takes full advantage of the data transmitted at various stages of the protocol. By guaranteeing the freshness of authentication messages, the authenticity of the generator of authentication messages, and the completeness of the authen...

The growing popularity and application of Web services have led to increased attention regarding the vulnerability of software based on these services. Vulnerability testing examines the trustworthiness and reduces the security risks of software systems. This paper proposes a worst-input mutation approach for testing Web service vulnerability based on Simple Object Access Protocol (SOAP) messages. Based on characteristics of SOAP messages, the proposed approach uses the farthest neighbor conc...

The weight hierarchy of a [n,k;q] linear code C over F_q is the sequence (d₁,...,d_r,..., d_k) , where d_r is the smallest support weight of an r-dimensional subcode of $C$. In this paper, by using the finite projective geometry method, we research a class of weight hierarchy of linear codes with dimension 5. We first find some new pre-conditions of this class. Then we divide its weight hierarchies into six subclasses, and research one subcla...

The widespread use of Location-Based Services (LBSs), which allows untrusted service providers to collect large quantities of information regarding users' locations, has raised serious privacy concerns. In response to these issues, a variety of LBS Privacy Protection Mechanisms (LPPMs) have been recently proposed. However, evaluating these LPPMs remains problematic because of the absence of a generic adversarial model for most existing privacy metrics. In particular, the relationships between...

In the previous construction of attributed-based encryption for circuits on lattices, the secret key size was exponential to the number of AND gates of the circuit. Therefore, it was suitable for the shallow circuits whose depth is bounded. For decreasing the key size of previous scheme, combining the techniques of Two-to-One Recoding (TOR), and sampling on lattices, we propose a new Key-Policy Attribute-Based Encryption (KP-ABE) scheme for circuits of any arbitrary polynomial on lattices, an...

Infrastructure as a Service (IaaS) has brought advantages to users because virtualization technology hides the details of the physical resources, but this leads to the problem of users being unable to perceive their security. This defect has obstructed cloud computing from wide-spread popularity and development. To solve this problem, a dynamic measurement protocol in IaaS is presented in this paper. The protocol makes it possible for the user to get the real-time security status of the resou...

Several public-key encryption schemes used to solve the problem of ciphertext data processing on the fly are discussed. A new targeted fully homomorphic encryption scheme based on the discrete logarithm problem is presented. Public-key encryption cryptosystems are classified to examine homomorphic encryption. Without employing techniques proposed by Gentry such as somewhat homomorphic and bootstrapping techniques, or relinearization technique proposed by Brakerski et al., a new method called ...

Chosen Ciphertext Attack (CCA) security on the standard model is widely accepted as the standard security notion for the public key cryptosystem. The existing CCA-secure public key cryptosystems on the standard model are expensive in terms of efficiency and practicality. In this paper, an efficient and practical public key cryptosystem is presented over the group of signed quadratic residues. It is provably secure against CCA on the standard model. Furthermore, public verifiability for this s...

Network security requirements based on virtual network technologies in IaaS platforms and corresponding solutions were reviewed. A dynamic network security architecture was proposed, which was built on the technologies of software defined networking, Virtual Machine (VM) traffic redirection, network policy unified management, software defined isolation networks, vulnerability scanning, and software updates. The proposed architecture was able to obtain the capacity for detection and access con...

Malicious applications can be introduced to attack users and services so as to gain financial rewards, individuals' sensitive information, company and government intellectual property, and to gain remote control of systems. However, traditional methods of malicious code detection, such as signature detection, behavior detection, virtual machine detection, and heuristic detection, have various weaknesses which make them unreliable. This paper presents the existing technologies of malicious cod...

Polling system models have a wide range of important applications including time-sharing computer systems, industrial control, communications, and computer networks. In this paper, we propose a two-class priority-based polling system that uses gated and exhaustive services to achieve the priority-based scheme. This model is set up according to the method of the imbedded Markov chain theory and the generation function and explicitly analyzes key system performance characteristics including mea...

Scientific instruments and simulation programs are generating large amounts of multidimensional array data. Queries with value and dimension subsetting conditions are commonly used by scientists to find useful information from big array data, and data storage and indexing methods play an important role in supporting queries on multidimensional array data efficiently. In this paper, we propose SwiftArray, a new storage layout with indexing techniques to accelerate queries with value and dimens...

This study uses the Elaboration Likelihood Model (ELM) and social presence theory to examine the microblogging reposting mechanism. Subjective and objective data were collected from 216 respondents in a field experiment. The results indicate that information quality and source credibility of microblogging messages affect users' reposting intention by affecting their perceptions of the usefulness and enjoyment of the information. Perceived enjoyment has a greater impact on reposting intention ...