The Cisco Unity IP Media Gateway products are integration devices designed to offer a high-quality connection between Cisco Unity or Cisco Unity Connection servers and your existing traditional private branch exchange (PBX). The Cisco Unity PBX IP Media Gateway (PIMG) is an 8-port, stackable integration device that emulates a digital or analog phone (station) on the PBX side and connects to the Cisco Unity server over a LAN or WAN using the Session Initiation Protocol (SIP).