一种自可信的匿名公平电子支付协议

针对电子商务中客户、商家和第三方的信任问题,在Brands离线电子货币方案基础上,利用同时生效签名生效的同时性,设计了一种简单、高效的自可信匿名公平电子支付协议.协议无可信第三方,但也可保证交易双方公平交换,并能及时地让交易双方各得所需.分析和实验表明,协议在满足自可信性同时,还满足安全性、客户匿名性、可追究性、公平性...     

一个基于多方的公平交换协议

基于秘密共享技术,提出一种有效的多方公平交换协议.该协议使用一个在线的可信第三方(TTP)来帮助参与者实现公平交换.使用在线的TTP协议的优势在于在线的TTP是半可信的.协议的公平性也得到证明.     

基于椭圆曲线的公平交换协议

基于椭圆曲线密码体制,提出了一个数字签名方案,并据此建立了一个适用于电子商务的公平交换协议,该协议通过在交易双方之间建立一个安全承诺作为凭证交换数字签名,以达到摆脱可信第三方参与的目的。此公平交换协议具有一般椭圆曲线密码体制密钥较短、安全性能良好的特点,能够摆脱第三方参与,提高运行效率,并同时保证交换双方的模糊性。分析证明,该协议具有可验证性、不可否认性、不可滥用性以及公平性等特点。     

恶意模型下公平的安全两方计算协议

安全多方计算通过参与者自行进行信息交互和计算完成,信息交换和计算对协议的公平性有很大影响。在恶意模型下基于m/2-out-of-m方法和知识承诺方案,提出一种两方公平交换协议,并用该协议构造一个满足公平性的安全两方计算协议。     

新的可验证加密方案及其应用

由于越来越多的电子商务在 INTERNET上执行 ,公平交换协议也就变得越来越重要 .可验证加密是公平交换协议重要的基础之一 ,所以设计好的可验证加密方案对公平交换协议的实现至关重要 .本文提出了一种全新的公开可验证加密方案 ,并在此基础上设计了一个适用于半可信第三方的公平交换协议的盲化可验证加密方案 .这两种方案简单、高效、易于实现     

CMAD-XCP:一种防御XCP协议公平性攻击的协同机制

针对XCP(eXplicit Congestion Protocol)协议分析公平性攻击的方法和特性,提出一种协同式路由器监控机制CMAD-XCP(XCP with Cooperative Malicious Attacker Detection)。CMAD-XCP由核心路由器感知恶意攻击,由边缘路由器实施对恶意流的区分和惩罚。仿真结果表明,CMAD-XCP可以及时、有效地惩罚恶意流,保护XCP协议的公平带宽分配,同时有效避免不公平竞争导致的网络拥塞。     

一种无证书的公平交换协议

公平交换协议是电子商务活动的一种重要安全协议.基于无证书密码体制,首先设计了一种无证书的可验证加密签名方案;然后基于该可验证加密签名方案构建了一种无证书的公平交换协议.协议降低了密钥托管和证书管理的开销,且满足有效性、公平性、时限性和优化性.     

无滥用的三方合同签署协议

针对目前三方合同签署协议中安全性与效率性的问题,利用可验证加密的变色龙签名(verifiable encryption of chameleon signatures,VECS)技术,设计了一个高效的无滥用的三方合同签署协议。理论分析结果表明,该协议同时满足完整性、公平性、无滥用性、可追究性、第三方 (TTP) 的不可见性和TTP合同保密性。而且与以前的三方合同签署协议相比,所设计的协议减少了合同签署方之间交互的轮数及发送消息的数量,因此效率更高。     

基于纠缠交换的量子安全多方求和

提出了一个基于纠缠交换的量子安全多方求和协议,该协议允许多个参与方安全地计算其秘密数据的和.在该协议中,引入了一个半可信的第三方来帮助这些相互不信任的参与方实现这个安全任务.利用d级cat态和Bell态的纠缠交换,在参与者和半可信第三方之间安全地传输信息.最后,安全分析表明该协议对几种常见攻击的安全性,在理论上是安全的...     

有效防御DDoS攻击的密钥交换协议的设计研究

针对现有密钥交换协议在保护通信双方身份信息和防御DDoS攻击方面的不足,提出一种在可信任第三方的辅助认证下实现的新型密钥交换协议．研究分析表明该协议能有效地保护双方通信实体的身份信息和防御DDoS攻击．     

A protocol for fair electronic purchase based on concurrent signatures

E-commerce protocols for the electronic purchase of goods are difficult to design and implement due to their complexity and high security demands. Fairness of such protocols in literature highly depends on an additional TTP（trusted third party）. However, it is difficult to find such a TTP in some situations. In addition, fairness for customers has been neither fully considered nor well satisfied in existing electronic purchasing protocols. In this paper, a new protocol FEP （fair electronic purchase） without a special TTP but an online bank is presented based on a concurrent digital signature scheme. The FEP protocol guarantees fair electronic purchase of goods via electronic payment between consumers, merchants and their online banks. The protocol is practical and the analysis based on the game logics shows that it achieves the properties of viability, fairness, and timeliness.     

A time sequence protocol to achieve the effect of fair exchange without trusted third party

A fair exchange protocol allows two parties to exchange items in a fair way, such that either both parties obtain the other＇ s item or neither party does. In this paper, we propose a time sequence protocol for exchanging partici- pants＇ warrants without a trusted third party （TTP）. Then, each participant is able to sign a proxy signature on behalf of its opponent. Owing to the proxy signature＇s restriction, the scheme achieves the desired effect of fair exchange of digital signatures. Our scheme is based on a time sequence rather than computation, and can be realized without the use of a TTP, thus differing from the existing fair exchange schemes. Compared with a concurrent signature, the proposed scheme does not need to release a keystone to wake the signatures when they exchange information fairly. The only advantage to the initial party is that it has the right to determine whether the exchanged warrants are valid before a designated time. However, because of the properties of proxy signatures, the initial party ultimately derives no benefit from this advan- tage. After the designated time, there is no additional advantage to benefit the initial party.     

基于二次剩余的最优公平电子商务交换协议

设计了一个可适用于计算机网络如Internet上进行电子货物交易的高效最优公平电子商务协议.考虑到现有的电子支付手段的实际使用情况,协议中使用在线的电子支付系统.新设计的协议具有高效、实用、离线的TTP、真正公平、易于实现等优点.     

基于证书认证机制的公平文件交换协议的算法设计

在电子商务活动中,进行实时公平的文件交换具有非常重要的意义．本文利用证书认证机制中简单、快速且交换活动脱离等特点,结合RSA算法构造出具备实时公平交换功能的文件交换协议．同时根据测试数据对该协议的各项性能与其它类似协议进行了简要分析．最后提出了可行的协议假定的实现流程．     

A Forward Integrity and Itinerary Secrecy Protocol for Mobile Agents

0 IntroductionMobile agents are programs that can autonomously mi-grate from host to host in a network. Mobile agenttechnologies are expectable as distributed processingtechnolo-gy of the next generation. Moreover , many agent systemshave appeared bythe spread of Java. Mobile agents are an ef-fective choice for many applications ,for several reasons[1 ,2],including i mprovements in latency and bandwidth of client-server applications and reducing vulnerability to network dis-connection.When ca…     

Fair non-repudiation for web services transactions

To safeguard the interests of transacting parties, non-repudiation mechanisms need to assure fairness and timeliness. The non-repudiation service currently implemented usually does not consider the requirement of fairness and the fair non-repudiation protocols to date can not be suitably applied in real environment due to its complex interaction. This paper discusses the transaction-oriented non-repudiation requirement for Web services transaction, analyzes the constraints of the traditional model for the available fair non-repudiation protocols and designs a new Online-TTP fair non-repudiation protocol. The new protocol provides a fair non-repudiation solution to secure Web services transactions and can be embedded into a single Web service call. The protocol adopts evidence chained to decreasing the overhead of evidence verification and management and alleviates the overhead of certificate revocation checking and time-stamp generation for signatures. The protocol has strong fairness, timeliness, efficiency and practicability.     

A resource-fair protocol for two-party coin toss

Coin-flipping protocols allow mutually distrustful parties to generate a random bit with uniform distribution.Minimizing bias and keeping fairness are two key requirements in designing such protocols.However,the best previously known fair coin-flipping protocol only guarantees with bias Ο(1 /r).In the paper,we introduce a new approach for fair coin-flipping protocol construction by using Garay et al’s "resource fairness" technique and propose a resource-fair two-party coin-flipping protocol according to the standard real/ideal simulation paradigm.Compared with the other coin-flipping protocols,our protocol enjoys an important advantage that its bias is 0.     

不可否认协议形式化分析的SVO逻辑方法

使用SVO逻辑对Zhou-Gollmann的公平不可否认协议的一个改进协议进行了形式化分析．在分析该协议的过程中,分析了使用SVO逻辑分析不可否认协议时存在的一些问题,这是分析过程无法发现Zhou-Gollmann不可否认协议的原因．这些问题包括协议目标的确定,协议时限性的描述与分析,协议初始假设集的确定等．分析协议时,不仅需要证明协议的最终目标,还需要证明中间目标．通过对SVO逻辑的语法进行扩展,使其具有显式的时间描述能力,从而能够分析不可否认协议的时限性．