Topic Last Modified: 2011-03-21

A SIP/CSTA gateway is a gateway between SIP and a computer-supported telecommunications application (CSTA). A SIP/CSTA gateway provides the interface between an existing private branch exchange (PBX) and Lync Server for routing remote call control requests to the PBX. After you install a SIP/CSTA gateway, you must perform the following procedures on each Lync Server pool for which you want to configure remote call control: