Waterfall’s unidirectional technology is recommended by many governmental and regulatory bodies worldwide as best practice in Industrial Control Systems (ICS) and Critical Infrastructure (CI) cyber security. See below for a few examples of a growing list of recommendations.
Unidirectional gateways limit the propagation of malicious code (ISA SP-99-3-3)
NEI exempts unidirectional-protected sites from 21 of 26 cyber-perimeter rules
ANSSI cybersecurity for ICS – many requirements for hardware-enforced unidirectionality
ENISA – unidirectional gateways provide better protection than firewalls
DHS recommends unidirectional gateways in security assessments
Unidirectional gateways limit propagation of malicious code (IEC 62443-3-3)
NRC exempts unidirectional-protected sites from 21 of 26 cyber-perimeter rules
NERC-CIP exempts over 35% cyber security requirements when using unidirectional gateways
ACSC recommends unidirectional communication between networks at different security levels