ScreenOS
ScreenOS is a real-time embedded operating system for the NetScreen range of hardware firewall devices from Juniper Networks. == Features == Beside transport level security ScreenOS also integrates these flow management applications: IP gateway VPN management – ICSA-certified IPSec IP packet inspection (low level) for protection against TCP/IP attacks Virtualization for network segmentation == Possible NSA backdoor and 2015 "Unauthorized Code" incident == In December 2015, Juniper Networks announced that it had found unauthorized code in ScreenOS that had been there since August 2012.