CacheGuard-OS

CacheGuard-OS is an open source operating system that turns hardware or virtual machines into unified threat management (UTM) appliances for network security. It integrates multiple open source components to provide firewalling, proxying, VPN, DHCP, QoS, and secure web management interfaces, focusing on easy deployment and configuration of network security functions, including support for VLANs, PPPoE, and authentication.