Symptoms
This article describes an update that adds 10-second timers to Microsoft Lync Server 2010 Outbound Routing (OBR) components. The timers are used to improve efficiency when the OBR components route Public Switched Telephone Network (PSTN) calls. The timers start when the OBR components send INVITE requests to PSTN calls. If the OBR components do not receive a PSTN gateway response within 10 seconds, the OBR components route the calls to other PSTN gateways.
Resolution
To resolve this issue, install the following cumulative update:
2592292 Description of the cumulative update for Lync Server 2010: August 2011
More Information
For more information about the Outbound Routing components, visit the following Microsoft website:
General information about the Outbound Routing components
For more information about SIP trunking, visit the following Microsoft website: