分裂认证码与纠错码

引入I-t-分裂认证码的概念。由有分裂的认证码得到纠错码,说明了当替换攻击成功的极大概率等于冒充攻击成功的极大概率时,信源数随编码规则数增大成线性增加,这一结论在无分裂认证码的情况下也成立。     

基于纠错码的CARTESIAN认证码的构造

本文给出了纠错码的构造Ｃａｒｔｅｓｉａｎ认证码的一种新的方法,计算了有关参数,并给出了一种构造具有大的源状态数量的认证码的方法。     

基于纠缠辅助码的量子模糊承诺和生物认证

本文针对经典模糊承诺体制不能有效抵抗量子算法攻击的问题,在纠缠辅助量子纠错码的基础上,结合量子哈希构造一类新的量子模糊承诺体制.利用无需自对偶约束的量子纠错码空间构建模糊承诺集产生承诺阶段所需的码字,并对其施加用于模糊证明的加噪变换,有效抵抗量子傅立叶取样攻击;提出一种量子哈希,对随机量子序列进行混淆扩散后加密,实现信息论意义上的一次一密安全.据此构建的量子模糊承诺体制可有效抵抗量子图灵机攻击.该文还给出了基于量子模糊承诺的挑战响应生物认证方案,分别对量子模糊承诺和生物认证方案在量子计算环境下的安全性作了分析,证明了其安全性和有效性.     

一种新型的信道纠错编码——之型码

提出了一种新型的纠错码－之型码,它可形成非常简捷的罗软输入／软输出译码规则,而且仿真结果表明,其性能在误比特率为10^-5处距香农理论极限仅0．9dB。     

Security Issues in Ultralightweight RFID Authentication Protocols

Wireless Personal Communications - Ultralightweight RFID authentication protocols have attracted much attention from both fields of science and industry in recent years due to their high...     

Untraceability Analysis of Two RFID Authentication Protocols

With the development of Radio frequency identification (RFID) technologies,theoretical study on the protocol's design promotes the increasing reality applications of this product.The protocol designers attach significance to untraceability analysis on key-update RFID authentication protocols.This paper analyzes two RFID authentication protocols in terms of forward untraceability and backward untraceability,which are two necessary conditions for key-update RFID protocols and ownership transfer protocols.This paper introduces impersonation attacks as well as desynchronization attacks to two protocols.This paper presents two enhanced protocols,which can achieve forward untraceability and backward untraceability privacy.This paper shows the outstanding efficiency and security properties of two improved schemes through detailed analysis and comparisons.     

Simulation-Based Traceability Analysis of RFID Authentication Protocols

Nowadays low-cost RFID systems have moved from obscurity into mainstream applications which cause growing security and privacy concerns. The lightweight cryptographic primitives and authentication protocols are indispensable requirements for these devices to grow pervasive. In recent years, there has been an increasing interest in intuitive analysis of RFID protocols. This concept has recently been challenged by formal privacy models. This paper investigates how to analyse and solve privacy problems in formal model. First, we highlight some vague drawbacks especially in forward and backward traceability analysis and extend it in the simulation-based privacy model family. Then, the privacy weaknesses of three new-found RFID authentication protocols are analysed in formal privacy models and three improved protocols are proposed to prevent the aforementioned attacks.     

Memory Reliability Improvement Based on Maximized Error-Correcting Codes

Error-correcting codes (ECC) offer an efficient way to improve the reliability and yield of memory subsystems. ECC-based protection is usually provided on a memory word basis such that the number of data-bits in a codeword corresponds to the amount of information that can be transferred during a single memory access operation. Consequently, the codeword length is not the maximum allowed by a certain check-bit number since the number of data-bits is constrained by the width of the memory data interface. This work investigates the additional error correction opportunities offered by the absence of a perfect match between the numbers of data-bits and check-bits in some widespread ECCs. A method is proposed for the selection of multi-bit errors that can be additionally corrected with a minimal impact on ECC decoder latency. These methods were applied to single-bit error correction (SEC) codes and double-bit error correction (DEC) codes. Reliability improvements are evaluated for memories in which all errors affecting the same number of bits in a codeword are independent and identically distributed. It is shown that the application of the proposed methods to conventional DEC codes can improve the mean-time-to-failure (MTTF) of memories with up to 30 %. Maximized versions of the DEC codes are also proposed in which all adjacent triple-bit errors become correctable without affecting the maximum number of triple-bit errors that can be made correctable.     

Scalability and Security Conflict for RFID Authentication Protocols

RFID technology continues to flourish as an inherent part of virtually every ubiquitous environment. However, it became clear that the public—implying the industry—seriously needs mechanisms emerging the security and privacy issues for increasing RFID applications. As the nodes of RFID systems mostly suffer from low computational power and small memory size, various attempts which propose to implement the existing security primitives and protocols, have ignored the realm of the cost limitations and failed. In this study, two recently proposed protocols—SSM and LRMAP—claiming to meet the standard privacy and security requirements are analyzed. The design of both protocols based on defining states where the server authenticates the tag in constant time in a more frequent normal state and needs a linear search in a rare abnormal states. Although both protocols claim to provide untraceability criteria in their design objectives, we outline a generic attack that both protocols failed to fulfill this claim. Moreover, we showed that the SSM protocol is vulnerable to a desynchronization attack which prevents a server from authenticating a legitimate tag. Resultantly, we conclude that defining computationally unbalanced tag states yields to a security/scalability conflict for RFID authentication protocols.     

Security Enhanced RFID Authentication Protocols for Healthcare Environment

RFID technology, which is concerned as one of the core technologies of Internet of Things, has been widely deployed in healthcare environment and brings a lot of convenience for people’s daily life. However, the security and privacy challenges of RFID authentication protocols are receiving more and more attention. One of the problems is that the current RFID protocols usually use a backend server to store the detailed information of tagged objects, which may lead to the issue of information leakage if the server is hacked or attacked by the adversary. To address this challenge, in this paper, we propose a security enhanced RFID authentication protocol for healthcare environment using the technique of indistinguishability obfuscation, which prevents the leakage of sensitive data from the backend server. Meanwhile, we extend the protocol to fit for the scenario of cloud environment where the tags’ information is stored in the cloud server. To our knowledge, our protocols are the first applications of indistinguishability obfuscation in the field of RFID authentication system. Moreover, our protocols are scalable and practical, and they are analyzed to achieve most of the security properties of the RFID system.

     

ECOC多类分类研究综述

纠错输出编码能有效地将多类问题转化为二类问题进行求解,已受到国内外从事机器学习的研究者们的重视,并使其成为多类分类领域的研究热点.本文首先分析了ECOC多类分类的原理和框架,指出解决ECOC多类分类问题的关键在于解码策略和编码策略的确定;然后从这两个关键点出发综述了ECOC多类分类的最新进展和应用领域;最后指出了目前存在的问题以及下一步研究方向.论文研究成果将为基于ECOC多类分类方法在实际应用过程中起借鉴和参考作用.     

纠错码数字签名方案的修正

对基于纠错码基础上构造的Xin-mei数字签名方案进行了修正,并指出在目前已知攻击方法下修正方案是安全的.     

一种基于相互认证的安全RFID系统

论文分析了现在RFID面临的各种安全问题,然后在XingxinGao等给出的RFID系统的基础上,提出了一种基于相互认证的安全RFID系统。通过结合相互认证机制与随机读取访问控制,本系统可有效地抵御传统攻击,特别是解决了Gao系统的重放攻击漏洞,也保证了个人隐私安全。此外,通过数字证书加密,标签与读头之间的信息交互过程变得更加安全。     

一种基于Hash函数的RFID安全认证方法

近年来,射频识别(RFID)技术得到越来越多的应用,随之而来的是各种RFID安全问题。对现有的基于Hash函数的RFID认证协议进行分析,针对现有技术存在的不足,提出了一种基于Hash函数的低成本的RFID双向安全认证方法,该方法只需要进行一次Hash函数计算,且加入了标签ID动态更新机制,通过在后台数据库中存储旧的标签ID解决同步问题,与现有技术相比具有一定的优越性。     

一种基于零知识证明的RFID鉴别协议

电子标签将取代条码的地位,但由于低成本的电子标签只具有很弱的计算能力,甚至不能完成基本的对称密钥加密操作,为其提供安全性存在一定困难。讨论了在射频识别(RFID)技术中存在的安全性风险,指出了应用身份鉴别协议的必要性,分析了目前广泛应用的两种鉴别体制的缺陷,提出了一种适合于RFID技术的基于零知识证明的鉴别协议,并对其进行了验证和性能分析。     

基于数据缓存机制的RFID安全协议

随着射频识别技术更为广泛地应用于人们的日常生活,安全和隐私问题越来越受到人们的关注。为了寻求一种更好的安全机制,本文首先对现有的安全机制进行了分析,指出了其不足,并将数据缓存机制应用于解决现有的几种安全隐患,讨论了机制的有效性和灵活性。应用分析表明,基于数据缓存机制在射频识别技术系统安全防护应用中适用性强,具有很好的应用前景。     

基于非齐次线性方程组的认证协议的改进

文中主要回顾了<基于非齐次线性方程组的认证协议的研究>一文中给出的基于具有无穷多个解的非齐次线性方程组而建立的一个身份认证协议和一个消息认证协议,结合<两个认证协议的安全缺陷>一文,对这两个认证协议中存在的安全缺陷进行具体分析;然后通过引入陷门单向函数对这两个认证协议进行改进,保障其安全缺陷和可操作性;并用RSA算法作为实例,对改进后的认证协议进行讨论分析.     

Performance of Error-Correcting Codes on Channels with Memory

Most magnetic recording and many other digital communication channels exhibit statistical dependencies among errors. The design of error-control schemes for such channels .requires proper models and tools that can be used to evaluate error performance after decoding. In this paper a simplified partitioned model of a channel with memory suggested by B. D. Fritchman is considered. This model is used to derive expressions for block and bit error probability bounds for major block burst-error-correcting codes: interleaved, single burst-correcting, and nonbiuary codes. The model-based bounds are compared to the experimental ones using the data obtained for helical scan magnetic tape recorders. The comparison showed an agreement between experimental and analytical data within one order of magnitude, with the average difference being as small as 16 percent in some cases. A simple and effective implementation of a multiple burst-error-correcting scheme based on the majority-logic decoding of interleaved binary codes is suggested. The scheme requires about ten off-the-shelf IC's for both encoder and decoder with the interleaving degree up to 512.     

A Novel Authentication Management RFID Protocol Based on Elliptic Curve Cryptography

The existing RFID (Radio Frequency Identification) security protocol lacks the key establishment mechanism, assuming only that both parties of the authentication protocol have shared their respective session keys. However, key establishment is an integral part of the RFID security system. This article first introduces the elliptic curve related mathematical theory foundation. Then we establish the key negotiation mechanism, and analyze the correctness and rationality of the negotiation mechanism. Finally, we design the authentication protocol based on elliptic curve in mobile RFID system, analyze the protocol authentication process, and compare the security and performance with other protocols, which shows that the authentication protocol has more efficient performance and the ability to resist all kinds of attacks.