# Siemens iSDX MSDN/DPNSS Interworking

## Description

MiVoice Business supports MSDN/DPNSS features for PSTN calls that are received from a Siemens iSDX PBX. However, after the iSDX PBX delivers a PSTN call to MiVoice Business, it activates a call completion timer. If this timer expires before the call is answered at the MiVoice Business system, the iSDX PBX clears the call and redirects it to a local extension, typically an operator on the iSDX. To prevent this timer from redirecting calls that use MSDN/DPNSS features, such as call forwarding and system rerouting, you must configure MiVoice Business to interwork with the Siemens iSDX.

MiVoice Business can be the destination node of the PSTN calls or it can act as a gateway node to other MiVoice Business destination nodes in a network or cluster. If the gateway node is configured to interwork with the iSDX PBX, the other MiVoice Business nodes in the network or cluster will interwork with the iSDX PBX as well.

### Siemens iSDX MSDN/DPNSS Interworking

## Conditions and Feature Interactions

- The MiVoice Business systems (gateway and destination nodes) must have 3300 ICP Release 7.1 software or higher.

- The iSDX PBX must deliver the PSTN calls to the MiVoice Business system (gateway or destination node) over TDM MSDN/DPNSS trunks.

- iSDX DPNSS Interworking is supported for PSTN calls that are sent from the MiVoice Business gateway node over MSDN/DPNSS trunks, IP trunks, or XNET trunks to other MiVoice Business destination nodes in a network or cluster.

- iSDX MSDN/DPNSS Interworking is not supported for PSTN calls that are sent over ISDN trunks, QSIG trunks, SIP trunks, or other common-channel signalling PSTN trunks.

## Programming

To configure MiVoice Business to interwork with a Siemens iSDX PBX:

1. On the MiVoice Business gateway or destination node, go to the Digital Link Descriptors form ( ) for the TDM MSDN/DPNSS link.

2. Set the Vendor Inter-working Type field to "Siemens iSDX".

## Device Support

Not applicable

## Operation

- See MSDN/DPNSS Features