NYMBLE: Protecting the Privacy of Users in Anonymous Networks and Blacklisting Misbehaving Users
V. Deepti, Sarojini Benitta · 2012
Anonymizing networks hide the client's IP address and allow the client to access the internet. It protects the privacy of users but unfortunately some users have misused such networks for abusive purposes. Website administrators block the IP addresses of misbehaving users and as a result they block all the known exit nodes of the anonymizing networks, denying anonymous access to misbehaving and behaving users alike. Since the server does not identify individual user's activities all the users are blocked from accessing resources of the server from the particular anonymous network. In the proposed system the users are identified individually without revealing their identity. Nymble is the proposed system in which the servers can misbehaving users, thereby blocking users without compromising their anonymity. The system detects the misbehaving users and adds them to the blacklist. Thus the server can blacklist the misbehaving users without knowledge of their IP address and allows behaving users to connect anonymously. Those of the users in the blacklist are blocked from accessing the resources for a specified time that is set by the administrators. The proposed system has several important properties which overcomes the drawbacks of the existing system. The properties are anonymous authentication, backward unlinkability, subjective blacklisting, fast authentication speeds, blacklist sharing, rate limited anonymous connections, revocation auditability and also addresses Sybil attacks.