Billion PBX - new generation phone system working in IP-networks using SIP protocol. Billion PBX can be installed on usual office computer to create fully functional phone system over the LAN. Users will be able to make not only voice calls but also will have a whole range of additional features like call forwarding, voicemail, callback and many others. Installation and configuration simplicity, reliability, low hardware requirements, popular operating systems support, flexible pricing policy - this is why you need to choose Billion PBX. You will also enjoy friendly technical support and attention to customer's needs. You can try Billion PBX by downloading it from our web-site and installing on your computer. Unregistered version allows to make up to 2 concurrent calls no longer than 5 minutes. Main features: * Subscribers registration by SIP Registrar and RAS protocols, * Call routing by SIP and H.323, * Call authorization, * Additional call features: call forwarding, voicemail, call hold, group call, ringback tone, * Callback, * Subscriber self-service, * Call Data Records (CDR), * Embedded rating and billing, * Integration with external billing system, * NAT traversal, * IVR, * Report generation. Billion PBX provides convenient administrative web-interface allowing remote management.