Cisco Cisco Unified Customer Voice Portal 11.0(1)

 illustrates the ISN VoIP solution. The ISN components—shown centered in the 

“cloud”—consist of the following:

Application Server. A Web Server application which interprets messages from the Cisco ICM 
software and generates VXML documents that it uses to communicate with the Voice Browser. 

Voice Browser. Accepts incoming PSTN and IP telephone calls, makes requests to the Application 
Server, and acts upon VXML commands received from the Application Server. 

The prompt files to be played to the caller reside on the Media Server, an off-the-shelf Web Server. The 
Voice Browser uses HTTP requests to retrieve the prompt files it needs.

Independent of the ISN’s components, the NAM/ICM is the cornerstone for making call routing 
decisions as they progress through the network. To the NAM/ICM, the ISN is simply a VRU peripheral; 
this is true whether the network is classic PSTN, VoIP, or a combination of both. 

In the ISN solution, the Gateway serves to convert PSTN calls to H.323 VoIP.   Those calls are routed 
to a destination endpoint—the Voice Browser—using a Gatekeeper or another mechanism available to 
the Gateway. The Gateway passes information such as the called number to the ISN’s Voice Browser, so 
an application can be chosen.