The thesis will focus on the workings of the Tor anonymity network and explore the possibilities of gaining information about the network, its nodes and its users from captured network traffic. The student will choose an appropriate method of detecting traffic going to and from the Tor network and use it to create a Wireshark dissector capable of such detection. Another Wireshark dissector will be made for decrypting Tor traffic using information provided by a modified Tor client. The student will then operate an own Tor relay and capture and analyze its network traffic using the aforementioned tools. Further, the student will analyze possibilities how a traffic coming from a Tor exit node can be distinguished from other traffic from the Internet on a server.