A SIP (session initiation protocol) trunk carries voice, data, and video through a “trunk” that replaces copper telephone connections through the conventional PSTN (public switched telephone network), consolidating phone and internet service into a single digital line. In plain English, SIP trunking allows you to physically disconnect from your phone company, opening the door for digital, internet-powered options (read: VoIP). And unlike hardwired telephone lines, digital lines allow you to scale your phone solutions as your business grows.