Cisco Cisco Unified Customer Voice Portal 10.5(1)

This chapter contains information about:

Using ISN and IP Phones with Cisco CallManager.

Inbound routing.

Outbound routing.

It also describes some limitations that exist in the ISN Version 2.1 Voice Browser concerning interaction 
with VoIP endpoints. 

This chapter presents an overview of how the ISN uses Voice over IP Routing. For detailed information 
about the Voice over IP routing configuration process, see the Cisco Internet Service Node (ISN) 
Configuration and Administration Guide. 

The ISN can route calls to Cisco IP Phones, using the signaling services of the Cisco CallManager 
(CCM), which acts as an H.323 Gateway for the IP Phones. 

ISN Version 2.1 can also accept incoming calls from an IP Phone. In this case the CallManager connects 
directly to the ISN Voice Browser in ISN Comprehensive and ISN Queue and Transfer modes, and 
directly to the gateway in ISN Advanced Speech mode.

While the CCM is similar in some respects to Cisco Voice Gateways, there are also significant 
differences. For ISN purposes, the most noteworthy difference is that the CCM does not support DNS 
lookups. Thus, when no Gatekeeper is present, all call routing configuration is performed on the CCM.

For ISN to access IP Phones through CCM, certain configuration rules must be followed. Specifically, 
the ISN Voice Browsers must be defined as Gateways on CCM, which enables CCM to receive multiple 
calls from the Voice Browsers.

For instructions on how to define a Voice Browser as a Gateway, see the Cisco Internet Service Node 
(ISN) Configuration and Administration Guide.