Lync Express with both SIP Trunking and PSTN Failover


Lync Express 2.0 can be configured to place calls destined to the PSTN through the built in Session Border Controller (SBC), as well as failover to the VoIP Gateway if SIP based PSTN Gateways are down. Please consult the diagram below to understand the interconnections of Lync Express 2.0.

Adjunct to PBX SIP Trunk with Failover 2-0.png

In this scenario, it is important to note the roles required for the successful operation of Lync Express:

  • Active Directory Domain Controller
  • Lync Mediation Server with Front End Pool
  • VoIP Gateway through Netborder Express Gateway
  • Session Border Controller
  • Lync Edge Server
  • Reverse Proxy Server through IIS ARR