The DPNSS Service Interworking with Cisco CallManager Using QSIG Tunneling feature enables the integration of CCM into the legacy TDM PBX networks across the QSIG tunnel and will support the following features: Path Replacement, Call Completion, Message Waiting Indicator, Call Transfer, Call Diversion and Call ID Services.
In traditional TDM-based PBX telephony, call transfer and forwarding usually operate within the limited scope of a single PBX system and, therefore, are simpler operations. For example, you are often limited to call transfers between extensions on the same PBX only.
The Call transfer service supports call transfers between QSIG PBXs and the Cisco CallManager. It supports transfers between an IP phone connected to a CCM and a phone connected to a QSIG PBX.