When you receive an incoming call to your phone number, your other telephones (cell, home phone, car phone) will ring as well and the first one answered will be connected to the caller. Basically the call will be routed to all phone sets, which you will list in simultaneous ring option.
PBXMate software Sip Trunk for improving Audio Quality. Removes noise originated from external mobile phones or from the call center, keeps audio level at a comfortable level and removes echo.