TOT, a Fast Multivariate Public Key Cryptosystem with Basic Secure Trapdoor

In this paper, we design a novel one-way trapdoor function, and then propose a new multivariate public key cryptosystem called $\rm TOT$, which can be used for encryption, signature and authentication. Through analysis, we declare that $\rm TOT$ is secure, because it can resist current known algebraic attacks if its parameters are properly chosen. Some practical implementations for $\rm TOT$ are also given, and whose security level is at least $2^{90}$. The comparison shows that $\rm TOT$ is more secure than $\rm HFE$, $\rm HFEv$ and $\rm Quartz$ (when $n \ge 81$ and $D_{HFE} \ge 129$, $\rm HFE$ is still secure), and it can reach almost the same speed of computing the secret map by $\rm C^\ast$ and $\rm Sflash^{v2}$ (even though $\rm C^\ast$ was broken, its high speed has been affirmed)

A Simple and Efficient New Group Key Management Approach Based on Linear Geometry

A new fundamental and secure group key management approach with a group controller GC using the theory of polynomial functions over a vector space over finite field is developed, where each member in the group corresponds to a vector in the vector space and the GC computes a central vector, whose inner product with every member\u27s ID vector are identical. The central vector is published and each member can compute a common group key via inner product. The security relies on the fact that any illegitimate user cannot calculate this value without the legitimate vector, therefore cannot derive the group key. This approach is secure and its backward and forward secrecy can be guaranteed. The performance of our approach is analyzed to demonstrate its advantages in comparison with others, which include: 1) it requires both small memory and little computations for each group member; 2)it can handle massive membership change efficiently with only two re-keying messages, i.e., the central vector and a random number; 3) it is very efficient and very scalable for large size groups. Our experiments confirm these advantages and the implementation of our prototype presents very satisfactory performance for large size groups

A Versatile Multi-Input Multiplier over Finite Fields

Multiplication of three elements over finite fields is used extensively in multivariate public key cryptography and solving system of linear equations over finite fields. This contribution shows the enhancements of multiplication of three elements over finite fields by using specific architecture. We firstly propose a versatile multi-input multiplier over finite fields. The parameters of this multiplier can be changed according to the requirement of the users which makes it reusable in different applications. Our evaluation of this multiplier gives optimum choices for multiplication of three elements over finite fields. Implemented results show that we takes $22.062$ ns and $16.354$ ns to execute each multiplication of three elements over $GF((2^4)^2)$ based on table look-up and polynomial basis on a FPGA respectively. Experimental results and mathematical proofs clearly demonstrate the improvement of the proposed versatile multiplier over finite fields

Ubiquitous one-time password service using generic authentication architecture

Abstract. In this paper we exploit GAA to build a scheme that converts a simple static password authentication mechanism into a one-time password (OTP) system. The scheme employs a GAA-enabled user device with a display and an input capability (e.g. a 3G mobile phone) and a GAA-aware server. Most importantly, the device does not need to be user or server specific, and can be used in the protocol with no registration or configuration (except for the installation of the necessary application software). The system also fits well to the multi-institution scenario and hence enables the provision of ubiquitous and on-demand OTP services. Keywords: One-time password, Generic Authentication Architecture, mobile securit

Cardiovascular Risk Factors and its Transition: An Ongoing Cohort Study in Chinese Kazakhs

Studies on the prevalence of risk factors and the incidence for cardiovascular diseases (CVDs) are limited in Kazakh population. By incorporating nomads, farmers, and urban residents, aged 30 years or older, in a cohort study, we investigated the characteristics of cardiovascular risk factors and their temporal trends that arose from the urbanization and subsequent changes in the lifestyle in a Kazakh population with 1668 participants. We used current guidelines and the monitoring trends and determinants in cardiovascular disease (MONICA) standard to define cardiovascular events. Kazakhs had a high prevalence rate of hypertension (45.3%), and this prevalence was much higher than the national average in China. Prevalence of two or more risk factors was highest among urban people and lowest among nomads. Urban residents have the highest prevalence of hypercholesterolemia and obesity compared with farmers and nomads. However, unlike other studies, our data indicate that young men had the highest prevalence of dyslipidemia, and it decreased significantly thereafter. Crude rates of incidence and mortality for acute cardiovascular events were 742 and 194 per 100,000 people, respectively; the standardized rates were 926 and 272 per 100,000 people, respectively. The findings from this study demonstrate the pervasive burden of cardiovascular risk factors and the related acute cardiovascular events in Kazakhs, particularly BP in Kazakh nomads