网上考试系统安全性研究及其实现

发布时间：2019-06-22 17:02

【摘要】：随着当前网络技术的不断发展,高校教育信息化已显得越来越重要。远程教育作为教育信息化的重要组成部分被很多国家作为教育信息化的突破口。而作为远程教育重要组成部分的网上考试，更是提高工作效率、经济效益，发展和完善教育体系的必然选择。本文在深入分析现有网上考试系统的基础上，探讨了如何提高网上考试系统的安全性。论文第一部分为匿名答卷安全性，是利用群签名技术，实现在确定合法考生身份之后，在教师人工阅卷时对考生身份进行隐藏，而评分后公开考生身份，从而确保阅卷老师在评分时无法得知考生身份，保证评分的公正性。第二部分为系统中其他安全性。在网上考试系统中应用新的身份认证方式，引入加入随机数的双向认证方式。在考生及阅卷老师登陆时，进行双向认证，既对考生及阅卷老师的身份进行认证，同时对考试中心服务器进行认证，保证考试的安全性。此外选择遗传算法作为自动组卷算法，对生成试卷的速度有一定的保证。并根据组卷的特性对遗传算法的选择、交叉和变异算子作略微的改进，使组卷算法的空间复杂度更小，这样更容易得到期望的适应度值，即得到更为随机、科学、合理的试卷。利用自动组卷的功能，可以保证考试时试题的保密性，防止泄露。第三部分为系统设计与实现。从整体上对整个系统的设计进行了研究，包括系统的设计流程等。按照从考生注册到登录，组卷到答卷交卷，教师的阅卷评分，一直到考试中心登记成绩的流程进对系统行了实现。本文在网上考试系统中研究人工阅卷引发的匿名答题的问题，并利用群签名技术实现了考生的匿名答题，以保证在人工阅卷过程中的公正性。在考试前，首先对合法考生的身份进行验证，，阅卷老师阅卷时，实现对考生身份的隐藏，但是在公布成绩之后，又能够保证考生对自己所答的试卷无法抵赖，从而满足人工阅卷的公正性。本文设计的网上考试系统满足了远程教育的需求，具有一定的实用价值。同时本文研究的群签名技术、双向身份认证技术对于在电子政务、电子商务各个方面的应用也有广阔的发展前景，具有一定的实践意义。
[Abstract]:With the continuous development of network technology, educational informatization in colleges and universities has become more and more important. As an important part of educational informatization, distance education has been used as a breakthrough in educational informatization in many countries. As an important part of distance education, online examination is an inevitable choice to improve work efficiency, economic benefit, development and improvement of education system. Based on the deep analysis of the existing online examination system, this paper discusses how to improve the security of the online examination system. The first part of the paper is the security of anonymous answer paper, which uses group signature technology to hide the identity of the examinee after determining the identity of the legitimate examinee, and to disclose the identity of the examinee after scoring, so as to ensure that the teacher can not know the identity of the examinee and ensure the fairness of the score. The second part is other security in the system. A new identity authentication method is applied in the online examination system, and a two-way authentication method with random numbers is introduced. When the examinee and the marking teacher log in, the two-way authentication is carried out, which not only authenticates the identity of the examinee and the marking teacher, but also authenticates the examination center server to ensure the security of the examination. In addition, genetic algorithm is selected as automatic test paper generation algorithm, which can ensure the speed of generating test paper. According to the characteristics of test paper formation, the selection of genetic algorithm, crossing and mutation operator are slightly improved, so that the spatial complexity of test paper generation algorithm is smaller, so that it is easier to get the desired adaptability value, that is, to get more random, scientific and reasonable test papers. By using the function of automatic test paper formation, the confidentiality of the test questions can be guaranteed and the leakage can be prevented. The third part is the system design and implementation. The design of the whole system is studied as a whole, including the design flow of the system and so on. According to the process from examinee registration to login, from test paper formation to answer paper submission, teachers' marking score, until the examination center registration results into the system to achieve. In this paper, the problem of anonymous answer questions caused by manual marking is studied in the online examination system, and the anonymous answer questions of candidates are realized by using group signature technology to ensure the fairness in the process of manual marking. Before the examination, the identity of the legal examinee is verified first, and the identity of the examinee is hidden when the marking teacher reads the test paper, but after announcing the results, the examinee can not deny the test paper answered by himself, thus satisfying the fairness of the manual marking. The online examination system designed in this paper meets the needs of distance education and has certain practical value. At the same time, the group signature technology and bidirectional identity authentication technology studied in this paper also have broad development prospects for the application of e-government and electronic commerce, and have certain practical significance.
【学位授予单位】：湖南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TP393.08

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