Reference:
CS1708A-AT-G
8-Port USB - PS/2 VGA KVM Switch with USB Peripheral port. The CS1708A KVM switch is a control unit that allows access to multiple computers from a single PS/2 or USB console (keyboard, mouse, and monitor). A single CS1708A can control up to 8 computers. As many as 31 additional switches can be daisy-chained to each other, so that up to 256 computers can all be controlled from a single keyboard-monitor-mouse console. Additionally, a front panel USB port is available for each computer to access any peripherals connected to it on a one-at-a-time basis.