Multiple Observations for Secret-Key Binding with SRAM PUFs

We present a new Multiple-Observations (MO) helper data scheme for secret-key binding to an SRAM-PUF. This MO scheme binds a single key to multiple enrollment observations of the SRAM-PUF. Performance is improved in comparison to classic schemes which generate helper data based on a single enrollment observation. The performance increase can be explained by the fact that the reliabilities of the different SRAM cells are modeled (implicitly) in the helper data. We prove that the scheme achieves secret-key capacity for any number of enrollment observations, and, therefore, it is optimal. We evaluate performance of the scheme using Monte Carlo simulations, where an off-the-shelf LDPC code is used to implement the linear error-correcting code. Another scheme that models the reliabilities of the SRAM cells is the so-called Soft-Decision (SD) helper data scheme. The SD scheme considers the one-probabilities of the SRAM cells as an input, which in practice are not observable. We present a new strategy for the SD scheme that considers the binary SRAM-PUF observations as an input instead and show that the new strategy is optimal and achieves the same reconstruction performance as the MO scheme. Finally, we present a variation on the MO helper data scheme that updates the helper data sequentially after each successful reconstruction of the key. As a result, the error-correcting performance of the scheme is improved over time.     

电子商务中的PKI、SSL与SET的技术分析

PKI是目前在电子商务中安全传输方案，SSL和SET两种安全的电子交易协议，在网上交易中有着广泛地应用，是大多数在线支付所采用的支付协议。这里在探讨PKI、SSL、SET技术原理的基础上，对它们各自的作用、技术实现、工作漉程等进行了描述；对它们之间的联系、区别、应用范围进行了深入的分析。     

基于平滑熵的无条件安全秘密钥协商时的密钥速率

本文研究了基于平滑熵进行无条件安全秘密钥协商时的密钥速率，得出了通信双方可以以强密钥速率协商无条件安全的共享密钥的条件。     

Analysis of atmospheric effects on the continuous variable quantum key distribution

Atmospheric effects have significant influence on the performance of a free-space optical continuous variable quantum key distribution (CVQKD) system. In this paper, we investigate how the transmittance, excess noise and interruption probability caused by atmospheric effects affect the secret-key rate (SKR) of the CVQKD. Three signal wavelengths, two weather conditions, two detection schemes, and two types of attacks are considered in our investigation. An expression aims at calculating the interruption probability is proposed based on the Kolmogorov spectrum model. The results show that a signal using long working wavelength can propagate much further than that of using short wavelength. Moreover, as the wavelength increases, the influence of interruption probability on the SKR becomes more significant, especially within a certain transmission distance. Therefore, interruption probability must be considered for CVQKD by using long-signal wavelengths. Furthermore, different detection schemes used by the receiver will result in different transmission distances when subjected to individual attacks and collective attacks, respectively.     

基于二维超混沌序列的交替加密

文章提出了一种将二维超混沌系统生成的序列对明文进行交替加密的方法,同时采用多种方法对数据进行处理,产生密钥流。该算法有加密速度快、易于计算机实现、密钥空间大等优点。     

基于超混沌序列的分组密码算法及其应用

利用混沌现象的“蝴蝶”效应和难以预测性等特点，提出利用超混沌序列改进分组密码算法的思想，实现基于超混沌序列的DES（数据加密标准）和AES（高级加密标准）算法，给出改进算法用于加密文本和图像数据的应用实例，分析比较改进后的算法和传统分组密码算法在安全性和抗破译性方面的性能。研究表明，分组密码算法和超混沌序列技术结合能够进一步提高系统的安全性和抗破译性能。     

光放大器对空间量子通信系统性能的改进

为提升自由空间量子通信系统性能,以相敏放大器(PSA)和相位非敏感放大器(PIA)原理为基础,研究了在量子通信系统接收端分别加入PSA、PIA后的高斯调制连续变量量子密钥分发(CVQKD)模型,推导了相应的安全密钥率公式.当信号波长分别为810 nm、1550 nm和3800 nm时,仿真分析了系统受到集体攻击和个体攻...     

基于平滑熵的无条件安全秘密钥的提取

本文讨论了通信双方在公共信道上基于平滑熵进行无条件安全秘密钥协商协议来提取秘密钥时,窃听者在信息协调阶段获得的边信息对保密增强阶段所能提取出的秘密钥长度的影响,得出了以一定概率所协商的秘密钥长度.