Signaling Gateways

The first type of video integration that ever existed between Lync, or OCS, and third-party systems was achieved using a signaling gateway. In this scenario, a SIP trunk exists between a Lync pool and the third-party system’s control unit. This is not the same type of SIP trunk used with Mediation Servers for voice calls, nor is it defined and managed the same way. A Mediation Server does not proxy video as part of its back-to-back user agent (B2BUA) model, so video calls to other systems must be managed differently.