A cheap, safe, stable and easy to manage network telephone system has been successfully developed. The kernel of SIP server is Linux system. Through the web management interface and system vulnerabilities automatically upgrade allows companies or individuals to easily manage. You can use the extension supports SIP protocol for VoIP gateways, software phone, or App program for mobile phone. Can also be set from the web to connect multiple SIP servers, in addition to the original function, can also allow the extension of the SIP server belonging to different series to linked together. Users don’t need to use complex computer operations can be used, and also can save the international call charges for companies.