首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
不使用双线性对的无证书代理环签名方案   总被引:2,自引:0,他引:2  
对已有代理环签名方案进行分析,发现这些方案中大多都使用了昂贵的双线性对。为了解决这个问题,基于离散对数和无证书的优点,提出了一种不使用双线性对的无证书代理环签名方案。避免了基于身份密码体制中的密钥托管问题和基于证书密码体制中的证书存在问题,实现了原始签名人和代理签名人的完全匿名性。整个方案没有使用双线性对,计算成本低,安全性能好,实用性强。  相似文献   

2.
基于无证书密码体制提出了一种不含双线性对运算的无证书签名方案,该方案能够追踪恶意的私钥生成中心的恶意行为,达到了Girault的安全等级3,具有不可伪造性.  相似文献   

3.
在无证书的公钥密码体制下,提出了一个基于无证书的门限盲代理盲签名方案.将代理签名、盲签名还有门限签名有机的结合,既解决了代理者权利过大的问题,又保护了代理者的隐私.该方案满足正确性、强不可否认性、不可伪造性、盲性等性质.  相似文献   

4.
提出一个新的基于椭圆曲线离散对数问题的代理签名方案。新方案除满足代理签名的七条基本性质外,还对目前已有的代理签名方案中尚未很好解决的问题—代理权滥用进行了有效的控制。在新方案中,若代理签名人签名超过证书上规定的次数,则他的私钥就会被破解,从而真正做到了对签名代理权的控制。  相似文献   

5.
基于LRSW问题,以双线性映射为工具,提出一个新的群签名方案.方案由两个可信机构分别担当群主管GM和撤消主管RM.群主管GM负责为欲加入本群的用户颁发证书,使其成为合法的群成员;撤消主管RM可以打开群签名以识别签名人的身份.群成员的证书生成是基于LRSW困难问题,具有防伪造性.群签名是一个被盲化了的成员证书关于消息m的非交互式的零知识证明,因此,本方案在安全性方面满足群签名方案的安全特性.  相似文献   

6.
利用PKI提出了一种新的公钥认证方案,该方案针对移动终端计算速度慢、存储量小的特点,本着尽量减少移动终端计算量、节省存储空间的原则,引入"密钥短,安全性高"的椭圆曲线密码体制进行加密和签名,并对加密和签名算法精心选择;采用归属方辅助证明的方法,使移动终端不传递和验证证书;移动终端和接入认证服务器之间以及各接入认证服务器间不需要预先存在安全关联;认证服务器间也不需要有相同的公钥参数,增强了系统的扩展性。  相似文献   

7.
基于离散对数问题和单向函数的安全性,提出了一个新的安全的代理签名方案。方案引入授权文书和时间证书等概念,克服了代理人滥用权力的缺陷,使代理人只能在特定时间内进行次数一定的代理签名;新设计的算法,有效分离了实际签名权和代理签名权,克服了签名验证者不易理解所收到的签名究竟是某人自己的真实签名还是受人之托的代理签名的缺陷;最后对方案的安全性和算法效率进行了分析。结论表明,新方案是一个安全可行的代理签名方案,具有较好的理论价值和应用价值。  相似文献   

8.
目前已有的无证书盲签名方案都是基于因式分解和求离散对数难解问题的基础上提出的,在量子算法的攻击下是不安全的.针对这一问题,基于格提出一个无证书的盲签名方案.方案中私钥生成中心(KGC)利用陷门生成技术和矩阵采样生成用户的部分私钥,采用拒绝采样技术生成盲签名.经分析,方案满足正确性和盲性,并且在随机预言模型下,基于求解格...  相似文献   

9.
分别对已有文献提出的两种没有双线性对的无证书签名方案进行分析,发现王方案虽然算法简单.效率高,签名长度短,但安全性低;陈方案安全性虽高,但计算量大,效率较低,签名长度长,在要求带宽较低的无线网络环境中不实用.为克服两种方案的缺点,提出一种新的没有双线性对的无证书签名方案,新方案算法简单,效率高,签名长度较短,在离散对数...  相似文献   

10.
一、校园网PKI系统的具体规划 1.首先进行的是PKI系统的体系结构规划,而CA的体系结构规划是需要重点考虑的。最简单的体系结构是根CA直接颁发所有的证书,这就表明所有的证书申请请求都发给根CA,这种直接进入根CA的方案会产生严重的安全问题:  相似文献   

11.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

12.
一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/  相似文献   

13.
《海外英语》2007,(5):10-11
Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?  相似文献   

14.
《海外英语》2007,(4):36
There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.  相似文献   

15.
王菲 《华章》2007,(12):273-273
Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.  相似文献   

16.
裴水妹 《华章》2007,(11):196
Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.  相似文献   

17.
18.
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…  相似文献   

19.
《海外英语》2007,(4):8-9
城堡, 是欧洲典型的建筑之一, 每个城堡都有一个美丽的传说或是一段历史。从本期开始, 我们将推出“城堡之旅”, 带各位读者去浏览、观赏欧洲各地的城堡, 开始一段文化与历史的旅途!  相似文献   

20.
During interview with English majors, it was found that a majority of students expressed disappointment with their experience of English literature classes. Students' dislike of learning English literature appears to be the major problem of teaching English literature in China. Reader response approach is a good way to solve this problem. In this paper, I explain the rationale behind the reader response approach, such as its origin, definition, features, assumptions, and strategies. Then I illustrate how reader response approach works as a teaching strategy by presenting several teaching models. At last I evaluate its usefuiness for teachers and present the advantages of reader response approach in Chinese context.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号