Recently, teaching ethical hacking techniques has become a vital component of information security programs that aim to produce competent information security professionals. Students need exposure to offensive techniques developed usually by hackers, along with the defensive techniques. This is problematic since students need to work with tools that may pose threat to the stability and security of the laboratories' computers and live networks within academic institutions. In an attempt to overcome the aforementioned issue, this paper discusses an ethical educational platform, called DoS-VLab, that aims at allowing students experience common denial of service (DoS) attacks, in secure academic environment. DoS-VLab platform is based on virtualization technologies and GNS3 network simulator for building virtual networks. Compared to traditional physical laboratories, practices show that the DoS-VLab platform helped produce more lab practices within the students, reduced training hours required for implementing hands-on lab exercises, and resulted in higher completion rate of the hands-on lab exercises.