VoiceXML

VoiceXML (VXML) is a digital document standard for specifying interactive media and voice dialogs between humans and computers. It is used for developing audio and voice response applications, such as banking systems and automated customer service portals. VoiceXML applications are developed and deployed in a manner analogous to how a web browser interprets and visually renders the Hypertext Markup Language (HTML) it receives from a web server. VoiceXML documents are interpreted by a voice browser and in common deployment architectures, users interact with voice browsers via the public switched telephone network (PSTN).

The VoiceXML document format is based on Extensible Markup Language (XML). It is a standard developed by the World Wide Web Consortium (W3C).

VoiceXML applications are commonly used in many industries and segments of commerce. These applications include order inquiry, package tracking, driving directions, emergency notification, wake-up, flight tracking, voice access to email, customer relationship management, prescription refilling, audio news magazines, voice dialing, real-estate information and national directory assistance applications.

VoiceXML has tags that instruct the voice browser to provide speech synthesis, automatic speech recognition, dialog management, and audio playback. The following is an example of a VoiceXML document:

When interpreted by a VoiceXML interpreter this will output "Hello world" with synthesized speech.

Typically, HTTP is used as the transport protocol for fetching VoiceXML pages. Some applications may use static VoiceXML pages, while others rely on dynamic VoiceXML page generation using an application server like Tomcat, Weblogic, IIS, or WebSphere.

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