Providing hands-on experience by live exercises is essential for current IT security education. Therefore, Tele-Lab IT security, a web-based training system, is being developed at the University of Trier, Germany. It attempts to integrate a security laboratory on the Internet using well-managed virtual machines which allow students to gain experiences of security technologies and tools in a reliable and secure way. In this paper, its user interface and architecture as well as some security considerations are described.