How HyperVoice IP PBX system works?
A HyperVoice PBX consists of one or more SIP phones / VoIP phones, an IP PBX server and optionally ATA gateways. The IP PBX server is similar to a proxy server and acting as SIP clients registering with the SIP providers. When local user wishes to make a call, they ask the IP PBX to establish the connection. The IP PBX has a directory of all phones/users and their corresponding SIP address and is thus, able to connect an internal call or route an external call via either a VoIP service provider.