Voice over Internet Protocol (VoIP) phone systems enable businesses of all sizes to experience the productivity enhancing benefits of Unified Communications and rich feature sets. Most commonly used with SIP trunks for their cost savings and superior call quality, VoIP systems can also be paired with PSTN lines using built in FXO ports or an external FXO gateway. IP phone systems include professional features, including auto attendants, call queues, call recording, voicemail, mobile phone integration, workplace chat, and video conferencing to name a few.