Today's industrial equipment is connected over a network to communicate with external systems and make decisions without human intervention, making it vulnerable to cyberattacks and showing the importance of research. This study explored the implementation of a cloud-based virtual testbed for a smart factory for cybersecurity testing and research. As a first step, this paper reports on developing an environment with one programmable logic controller (PLC) simulating a conveyor belt setup. The study examined different virtualization platforms and network designs. In addition, it executed a denial-of-service attack and identified its signature indicators. The study found that VMware Workstation Pro is the most suitable virtualization platform and that network input and output are the DoS attack's signature indicators.