Voice Application with J2EE

I'm convinced that J2EE lightweight container architecture is the right way to go for the majority of voice applications. However, there needs to be some tweaks in the way the UI tier utilizes it, compared to what we're used to seeing with HTML-based applications.

The standard platform architecture for Voice Application is to have 100 or so browser instances sitting on a server. The browser is not located on the client, because the client is a POT (Plain Old Telephone). The caller dials up a computer with a Dialogic or NMS card, or a SIP gateway, and the call is routed to one of the browser instances running on a server. This may be the same server that's running the app server, or it may just be on the same LAN.

So now the browser cache becomes much, much more important. If I have a few thousand phone calls coming in every hour to those 100 browsers, and they're all running the same application, the absolute worst thing I can do is a lot of dynamic page rendering. That would involve parsing the JSP into VoiceXML, and parsing the VoiceXML into runnable code, on every request.

So, component libraries like Tapestry or JSF are out. MVC frameworks like struts could be okay, as long as they're redirecting to static VoiceXML pages, instead of forwarding to JSPs.