pfSense - pfSense is a free and open source firewall and router that also features unified threat management, load balancing, multi WAN, and more
NethServer - NethServer is an operating system for Linux enthusiasts, designed for small offices and medium...
SonicWall - SonicWall security solutions protects your network, systems, users and data from cyber threats.
ClearOS - A very good alternative for Windows Server, for free
MikroTik RouterOS - The main product of MikroTik is a Linux-based operating system known as MikroTik RouterOS.
FreeIPA - FreeIPA is an integrated security information management solution combining Linux (Fedora), 389...