Waterfall Unidirectional Security Gateways replaces firewalls in industrial network environments, providing absolute protection to control systems and operations networks from attacks originating on external networks. Unidirectional Gateway solutions come in pairs: the TX appliance contains a laser, and the RX appliance contains an optical receiver. The Gateway pair can transmit information out of an operations network, but is incapable of propagating any virus, DOS attack, human error or any information at all back into the protected network. This integration enables Idira to securely send information from the OT side of an ICS network to the IT side.