VoiceXML 2.0 reaches W3C milestone

While Microsoft touted the latest release of its SALT-based Speech Server at last week's SpeechTEK conference, a competing speech standard reached a milestone. The Voice Extensible Markup Language (VoiceXML) 2.0 received final 'recommendation' status from the World Wide Web Consortium (W3C).

VoiceXML is the standard scripting language for rendering Web pages over the telephone. The decision of the W3C to advance VoiceXML 2.0, along with the supporting Speech Recognition Grammar Specification (SRGS), to recommendation status effectively establishes them as Web standards. It means that the standards group considers the spec to be stable and that it contributes to Web interoperability. It also means that the W3C membership favors its adoption by the industry.

VoiceXML and SRGS are parts of the W3C's Speech Interface Framework, which is an evolving set of standards for building applications that let users interact with Web-based services over a telephone with a range of voice-based interfaces.

As a standard, VoiceXML has ''huge momentum,'' said Yankee Group analyst Art Schoeller, with VoiceXML 2.0-compliant products already on the market from core technology, platform, development-tool and hosted services providers.

Zelos Group senior analyst Dan Miller sees broad industry adoption of the standard. VoiceXML appeals to major speech-enabled enterprises, including financial services, travel and telcos, he said, because it ''carries with it the promise of reusable code and portability.''

According to the VoiceXML Forum, more than 10,000 commercial VoiceXML-based applications have been deployed worldwide for applications such as customer care, directory assistance, telematics and unified messaging. The industry organization was to promote VoiceXML, and is currently backed by some industry heavyweights, including AT&T, Hewlett-Packard, IBM, Lucent and Motorola. The group reports that more than 370 member companies are currently developing and deploying VoiceXML-based applications, products and services. Membership in the Forum is open to any interested company.

In support of the W3C announcement, the Forum disclosed plans to launch the VoiceXML Platform Certification Program in the next quarter. Currently in the pilot phase, the program consists of a series of tests to determine whether a VoiceXML platform is fully compliant with the latest release of the spec. According to Forum spokesperson Christian Danella, the program will test for compliance with the VoiceXML 2.0 Recommendation and the W3C's VoiceXML 2.0 Implementation Report.

The Forum wants to encourage VoiceXML platform vendors to submit their products for testing and certification, Danella said. Platforms will be certified on a first-come, first-served basis. To submit a platform for certification, visit the Forum's Web site at The group plans to list VoiceXML-certified platforms on the site.

About the Author

John K. Waters is a freelance writer based in Silicon Valley. He can be reached at


Upcoming Events


Sign up for our newsletter.

Terms and Privacy Policy consent

I agree to this site's Privacy Policy.