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.
InfiniRoute Networks Inc. provides fully managed Voice over IP (VoIP) peering services for wireline and wireless carriers who need PSTN-quality VoIP connections to high-growth traffic regions worldwide.