Juniper Contrail!

pfSense is a free, open source customized distribution of FreeBSD tailored for use as a firewall, and router. In addition to being a powerful, flexible firewalling and routing platform, it includes a long list of related features and a package system allowing further expandability without adding bloat and potential security vulnerabilities to the base distribution, making it a fully qualified UTM device. pfSense is a popular project with more than 1 million downloads since its inception, and proven in countless installations ranging from small home networks protecting a PC and an Xbox to large corporations, universities and other organizations protecting thousands of network devices. »

VyOS is a community fork of Vyatta , a Linux-based network operating system that provides software-based network routing, firewall, and VPN functionality.

The SmoothWall Open Source Project was set up to develop and maintain SmoothWall Express - a Free firewall that includes its own security-hardened GNU/Linux operating system and an easy-to-use web interface.

OpenContrail is an Apache 2.0-licensed project that is built using standards-based protocols and provides all the necessary components for network virtualization–SDN controller, virtual router, analytics engine, and published northbound APIs. It has an extensive REST API to configure and gather operational and analytics data from the system. Built for scale, OpenContrail can act as a fundamental network platform for cloud infrastructure. The key aspects of the system are: