Security Analysis of Pairing-based Cryptography

Recent progress in number field sieve (NFS) has shaken the security of Pairing-based Cryptography. For the discrete logarithm problem (DLP) in finite field, we present the first systematic review of the NFS algorithms from three perspectives: the degree $\alpha$, constant $c$, and hidden constant $o(1)$ in the asymptotic complexity $L_Q\left(\alpha,c\right)$ and indicate that further research is required to optimize the hidden constant. Using the special extended tower NFS algorithm, we conduct a thorough security evaluation for all the existing standardized PF curves as well as several commonly utilized curves, which reveals that the BN256 curves recommended by the SM9 and the previous ISO/IEC standard exhibit only 99.92 bits of security, significantly lower than the intended 128-bit level. In addition, we comprehensively analyze the security and efficiency of BN, BLS, and KSS curves for different security levels. Our analysis suggests that the BN curve exhibits superior efficiency for security strength below approximately 105 bit. For a 128-bit security level, BLS12 and BLS24 curves are the optimal choices, while the BLS24 curve offers the best efficiency for security levels of 160bit, 192bit, and 256bit.Comment: 8 figures, 8 tables, 5121 word

Does corporate social responsibility matter to management forecast precision? Evidence from China

This article investigates whether socially responsible companies differ from other firms in the quality of earnings forecasts issued by management. Specifically, using 5192 earnings forecast observations of 669 Chinese listed companies from 2010 to 2016, we examine whether companies that perform better in corporate social responsibility (CSR) still provide higher-precision management earnings forecasts compared with companies with poor CSR performance, thereby presenting an image of transparent and accountable disclosures. Through empirical research, this paper finds that CSR is positively associated with management forecast precision. This result is robust to using alternative measures of CSR, considering mandatory disclosure sample and voluntary disclosure sample, and controlling for potential endogeneity concern by adopting the instrumental variable method. Furthermore, we find the relationship between CSR and management forecast precision is stronger in non-state-owned firms. Our findings suggest that socially responsible companies will comply with higher ethical standards and hence maintain their well-established social reputation by disclosing high-quality earnings forecasts, which lends support to the transparent forecast hypothesis. This paper enriches the existing studies regarding the economic consequences of CSR and adds empirical evidence from emerging markets