Probabilistic Analysis of Onion Routing Networks Using PRISM

People require privacy when doing transaction via Internet connection. For example, some people do not want other people to know what web page they request. Anonymous cash is not anonymous anymore if the channel used for the connection identifies the identity of the participating entities. Email users sometimes want to hide their email addresses. These days, the Internet does not really care about privacy. Encryption is provided to protect privacy, but it only protects the content of a transaction. Thus an eavesdropper can still learn the IP addresses of the internet users to infer their identities. Special networks, called the anonymity network, were created to protect privacy, especially the identities of the entities participating in a communication via Internet connections. This paper discusses probabilistic analysis of the anonymity provided by anonymity networks, namely Onion Routing, by using a model-checker tool called PRISM.