The present invention presents apparatuses and systems for operating multiple computers from a single keyboard and a single mouse and view composite videos generated from video output of the multiple computers on a single display, while preventing any possible information leakage between the computers. Keyboard and mouse commands detected by a host controller are used to control a video processor and a peripheral switch. The peripheral switch directs keyboard and mouse signals to one selected host and at the same time, the video processor creates an active display window showing video information from the selected host. Physical unidirectional isolators in the video, keyboard and mouse channels prevent any potential data leakages between hosts.