Kerio Operator is a VoIP PBX phone system for small and medium businesses that delivers an intuitive admin interface and unmatched ease-of-use. Based on the industry-standard SIP VoIP protocol, Kerio Operator is compatible with any SIP device and provider, and it will even auto-configure the most popular phones. Kerio Operator is available both as a hardware appliance and a software appliance that installs from a disk image with its own custom operating system and everything else you need to be up and running in minutes.