Prevention of Sybil Attack using a Credential System in Anonymizing Networks

Users are allowed to access the anonymity network while they are blocked from tracing their identity on the internet. Tor is open-source anonymity software free to public use. Online anonymity moves Internet traffic through a network of servers. Traffic analysis and network surveillance are prevented by the networks which are anonymized or at least makes it more difficult. Website administrators can disable access to abuser by blocking their IP addresses. But when an abuser routes through an anonymizing network it is not practical to block the IP address. So, all the known exit nodes of anonymizing networks have been blocked by the administrators. As a result, anonymous access has been denied to both misbehaving and behaving users alike. A privacy maintaining system called Nymble has been developed to blacklist the misbehaving users and the security of the system is improved.