IVR Development

This section of our technical library presents information and documentation relating to IVR Development and custom IVR software and products. Business phone systems and toll free answering systems (generally 800 numbers and their equivalent) are very popular for service and sales organizations, allowing customers and prospects to call your organization anywhere in the country. The PACER and WIZARD IVR System is just one of many DSC call center phone system features..

What Is IVR?. An Interactive Voice Response (IVR) processes inbound phone calls, plays recorded messages including information extracted from databases and the internet, and potentially routes calls to either inhouse service agents or transfers the caller to an outside extension.

Contact DSC today. to learn more about our IVR services and IVR application development software.

A bottom up look at XML and VoiceXML.

By: Chris "Dr. CT" Bajorek

Question: "I have seen various things in print lately about voiceXML and was wondering how we could benefit from this technology inside our own company. We have a very active IVR system that handles automated orders and order tracking and we have a corporate web server. What's the big benefit if we use voiceXML, and does it make sense to try to retrofit voiceXML to our existing IVR system?"
-Steven W., Chicago, IL

Good question, Steven. I am seeing quite a bit in the news lately about this new technology. Let's explain things from the bottom up; first, a bit about XML. I've heard some suggest that XML, or "eXtensible Markup Language," is another web-centric markup language like HTML. Not exactly true. Actually, XML - defined in a true standard overseen by the World Wide Web Consortium (W3C) - is a syntax for creating markup languages that use descriptive tags to describe the information elements you are manipulating. Thus, XML allows you to build web-based information frameworks that precisely describe and relate to your particular data types. This makes it more adaptable and efficient than existing models like HTML.

The key is this: You are tagging information elements according to their use and meaning in your application, not according to their graphical display, as HTML's graphically-oriented "table," "center," and "bold" tags do, for example. This tagging allows other processes, which don't care at all about visual presentation, to easily operate on them. For more web developer-level information on XML, check out this page.

VoiceXML is a special markup language designed to facilitate the creation of interactive voice response (IVR) services. It enables the orientation of voice-based dialogs for telephone callers that feature the playing of speech prompts using pre-recorded and text-to-speech information, accepting spoken commands (via speech recognition) and touch tone inputs, and the recording of caller audio information.

The version 1.0 specification for VoiceXML was itself also submitted to the W3C in March 2000, so it's looking like a standard you can hang your hat on for at least awhile. The burning question with any new standard is, of course, how many vendors will actually adopt it and release products based on it. With the founding members of the VoiceXML Forum being AT&T, IBM, Motorola, and Lucent, and with some 150 other companies as official members so far, voiceXML is off to a good start. (For more information about the forum, head here. The official version 1.0 VoiceXML specification can also be downloaded from that site for free.)

Benefits of VoiceXML

So why should you create IVR applications based on voiceXML when existing IVR products work just fine? One significant reason: VoiceXML provides an intrinsic ability to access information stored on or accessed through a corporate web server. Since IVR systems generically require access to one or more corporate databases, any such database connectivity already implemented via a company web server is directly usable in a voiceXML script. This saves development time and money and can greatly reduce maintenance costs.

Another clear benefit is that existing web application development tools become mature tools for development of voiceXML-based IVR applications. Using such tools and development methodologies also frees up IVR application developers from low-level IVR platform or database access details. VoiceXML applications by their very nature have excellent portability across web server and IVR platforms that properly support the standard. This means you are free to change to other voiceXML-compliant IVR platform vendors without losing your development work.

VoiceXML Architecture

Here's a little about how voiceXML works under the covers. As shown in Figure 1, a document server (usually a web server) processes requests from a client application, the voiceXML interpreter, through the voiceXML interpreter context. The server replies with voiceXML documents that contain actual voiceXML commands that are processed by the voiceXML interpreter.

The voiceXML interpreter context may monitor caller inputs in parallel with the voiceXML interpreter. For example, one voiceXML interpreter context may always listen for a special touch tone command that takes the caller to a special menu, while another may listen for a command that changes the playback volume during the call.

The implementation platform contains the telephone hardware and related CT resources and is controlled by the voiceXML interpreter context and voiceXML interpreter. For instance, an IVR application may have the voiceXML interpreter context detecting an incoming call, reading the first voiceXML document, and answering the call while the voiceXML interpreter executes the first touch tone menu process after the call is answered. The implementation platform generates events in response to caller actions (e.g., touch tone or spoken commands) and system events (e.g., timers expiring). Some of these events are acted upon by the voiceXML interpreter itself, as specified by the voiceXML document, while others are acted upon by the voiceXML interpreter context.

What does a voiceXML application look like? Here is a voiceXML page fragment generated by a web application that implements a classical dtmf-based IVR menu:

For sports press 1, For weather press 2, For stock quotes press 3.

tag defines a caller menu structure. The tag queues a TTS resource for the IVR phone call and plays the bracketed text information as audio output to the user. If it was desired to play a pre-recorded audio prompt file instead, then the tag could have been used, as in:

.

It should also be mentioned that voiceXML also fully supports speech recognition as a method of accepting caller commands. As you can see, you do not need to be a low-level CT programmer to understand what's going on here. Of course, a complex voiceXML application can be much more involved than this simple example, but this example should be enough to give you a basic idea of how voiceXML applications are built using the tags.