期刊名称：International Journal of Computer Technology and Applications
电子版ISSN：2229-6093
出版年度：2012
卷号：3
期号：6
页码：2046-2052
出版社：Technopark Publications
摘要：In bio-medicine and other health-related fields a need for anonymous access to Grid resources has been identified. Anonymity networks such as Tor provide users with a means to communicate privately over the Internet without disclosing their IP addresses. But the success of such networks, however, has been limited by users employing this anonymity for abusive purposes, such as defacing Wikipedia. In such cases, the Anonymizing networks as intended should disable access to misbehaving users while providing anonymous connections to the honest users. But the anonymity provided by such networks prevents website administrators from blacklisting individual malicious users IP addresses. As a result, administrators block all network nodes. To solve this problem, a system called NYMBLE was introduced which can blacklist malicious users without the knowledge of their IP addresses while allowing honest users to connect anonymously. But Anonymous authentication scheme may be vulnerable to Sybil attacks if users can get new credentials after their issued credential is blacklisted. In this paper, it is discussed how the Sybil Attacks can be prevented in the Anonymizing networks using a Central Authority whose role is to ensure that each pseudonym belongs to some valid user.
