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

作　　者：He Du Jian Wang Yanan Liu 

机构地区：[1]College of Computer Science and Technology, Nanjing University of Aeronautics and Astronautics

出　　处：《Chinese Science Bulletin》2014年第7期699-702,共4页

基　　金：supported by Funding of Jiangsu Innovation Program for Graduate Education(CXZZ12_0161);the Fundamental Research Funds for the Central Universities;funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions ‘‘Internet of Things and Control Technology’’

摘　　要：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 participants' 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 advantage. After the designated time, there is no additional advantage to benefit the initial 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.

关 键 词：公平交换协议 时间序列 可信第三方 代理签名 数字签名 信息发布 TTP 参与者 

分 类 号：TP309[自动化与计算机技术—计算机系统结构] TN918.1[自动化与计算机技术—计算机科学与技术]