VoIP Technology uses SIP Trunking. SIP Trunk is similar to a phone-line, except that a SIP Trunk utilizes the IP network, not the PSTN. SIP Trunk are versatile and cost effective solution that delivers the benefits and cost savings of VoIP. You can now retain your existing IP PBX system and leverage your existing Internet connection for both voice and data. All you need is a VoIP provider which carries quality product with competitive rate. DIDforsale provides Inbound and Outbound SIP DID’s for 2600+ rate centers. Each DID comes with unbelievable 20 channels.