Performance Measurements and Statistics of Tor Hidden Services

Tor (the onion routing) provides a secure mechanism for offering TCP-based services while concealing the hidden server's IP address. In general the acceptance of services strongly relies on its QoS properties. For potential Tor users, provided the anonymity is secured, probably the most important QoS parameter is the time until they finally get response by such a hidden service. Internally, overall response times are constituted by several steps invisible for the user. We provide comprehensive measurements of all relevant latencies and a detailed statistical analysis with special focus on the overall response times. Thereby, we gain valuable insights that enable us to give certain statistical assertions and to suggest improvements in the hidden service protocol and its implementation.