World Wide Web Consortium Issues VoiceXML 2.0 and Speech Recognition Grammar as W3C Recommendations

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Critical components of the W3C Speech Interface Framework now complete

Testimonials -- 16 March 2004 -- Giving voice to the Web, the World Wide Web Consortium (W3C) has published VoiceXML 2.0 and Speech Recognition Grammar Specification (SRGS) as W3C Recommendations. The goal of VoiceXML 2.0 is to bring the advantages of Web-based development and content delivery to interactive voice response applications. SRGS is key to VoiceXML's support for speech recognition, and is used by developers to describe end-users responses to spoken prompts.

Today's announcement marks the advancement to Recommendation status of the first two specifications in W3C's Speech Interface Framework. Aimed at the world's estimated two billion fixed line and mobile phones, W3C's Speech Interface Framework will allow an unprecedented number of people to use any telephone to interact with appropriately designed Web-based services via key pads, spoken commands, listening to pre-recorded speech, synthetic speech and music.

"The completion of VoiceXML 2.0 and SRGS marks an exciting milestone in the convergence of telecom technologies and the Web. Historically, there were both technical and cultural gaps between the way voice-based systems have evolved and that of the Internet and Web, leaving the information available only to voice systems or the Web, " explained Tim Berners-Lee, W3C Director. " With the development of the W3C Speech Interface Framework, including VoiceXML 2.0 and SRGS, we're now able to integrate and benefit from the strengths of both groups - the power and impact of industrial research and broad product testing and deployment, and the extensibility and openness of technical solutions that are consistent with Web technical principles and can scale accordingly. "

A World Wide Web Consortium (W3C) Recommendation is understood by industry and the Web community at large as a Web standard. Each Recommendation is a stable specification developed by a W3C Working Group and reviewed by the W3C Membership. Recommendations promote interoperability of Web technologies of the Web by explicitly conveying the industry consensus formed by the Working Group.

VoiceXML 2.0 and SRGS Lay the Foundations for the W3C Speech Interface Framework

In the W3C Speech Interface Framework, VoiceXML controls how the application interacts with the user, while the Speech Synthesis Markup Language (SSML) is used for spoken prompts and the Speech Recognition Grammar Specification (SRGS) for guiding the speech recognizers via grammars that describe the expected user responses. Other specifications in the Framework include Voice Browser Call Control (CCXML), which provides telephony call control support for VoiceXML and other dialog systems, and Semantic Interpretation for Speech Recognition, which defines how speech grammars bind to application semantics.

VoiceXML 2.0 Delivers Voice and Interactivity to the W3C Speech Interface Framework

VoiceXML 2.0 allows developers to create audio dialogs that feature synthesized speech, digitized audio, recognition of spoken and Dual tone multi-frequency (DTMF, or touch-tone) key input, recording of spoken input, telephony, and mixed-initiative conversations. VoiceXML is downloaded from HTTP servers in the same way as HTML. This means that application developers can take full advantage of widely deployed and industry proven Web technologies.

"VoiceXML 2.0 has the power to change the way phone-based information and customer services are developed. No longer will we we have to press 'one' for this or 'two' for that. Instead, we will be able to make selections and provide information by speech," explained Dave Raggett, W3C Voice Browser Activity Lead. "In addition, VoiceXML 2.0 creates opportunities for people with visual impairments or those needing Web access while keeping their hands and eyes free for other things, such as getting directions while driving."

SRGS Drives Robust Recognition of User Responses

The Speech Recognition Grammar Specification--SRGS-- allows applications to specify the words and phrases that users are prompted to speak. This enables robust speaker independent recognition.

SRGS covers both speech and DTMF input. DTMF input is valuable in noisy conditions or when the social context makes it awkward to speak. Speech recognizers are generally able to report the degree of confidence -- that is, the likelihood of having correctly recognized the word or phrase - and may provide the most likely alternatives when the recognizer is uncertain as to which of them the user actually said.

SRGS is applicable to more than speech and has been successfully applied to handwriting recognition where the user input is a constrained set of words.

Adoption Rate of VoiceXML 2.0 and SRGS Already Industry Wide

In order to advance to W3C's Recommendation status, there must be evidence of independent interoperable implementations - it must be proven to work. In the case of VoiceXML 2.0, the implementation evidence is extraordinary, with at least eight known implementations in both prototype and fully released products. A complete list of current implementors is available. The implementation report for SRGS includes at least six complete, independent implementations.

There is an extensive, public test suite. While the initial version contained roughly 300 tests, the final version contains over 600 tests. This complements the test suite provided with the Speech Recognition Grammar Specification and the test suite for Speech Synthesis Markup Language which became a W3C Candidate Recommendation in December 2003. Test suites for the remaining specifications in the W3C Speech Interface Framework, including Semantic Interpretation for Speech Recognition and CCXML, are under development by the W3C Voice Browser Working Group and will be published over the next few months.

In addition to the continued work on the remainder of the Speech Interface Framework, the Voice Browser Working Group is already hard at work designing the requirements for the next major version of the dialog markup language, which will build upon the success of VoiceXML 2.0 and incorporate ideas from SALT, XHTML+Voice, and other W3C Member contributions.

The W3C Voice Browser Working Group is among the largest and most active in W3C. Its participants include: Aspect Communications, BeVocal, Canon, Comverse Technology, Convedia, ERCIM, France Telecom, HeyAnita, Hitachi, HP, IBM, Intel, IWA-HWG, Loquendo, Microsoft, MITRE, Mitsubishi Electric, Motorola, Nuance Communications, Openstream, SAP, Scansoft, Siemens, Snowshore Networks, Sun Microsystems, Telera, Tellme Networks, Verscape, Vocalocity, VoiceGenie Technologies, Voxeo, and Voxpilot.

About the World Wide Web Consortium [W3C]

The W3C was created to lead the Web to its full potential by developing common protocols that promote its evolution and ensure its interoperability. It is an international industry consortium jointly run by the MIT Computer Science and Artificial Intelligence Laboratory (CSAIL) in the USA, the European Research Consortium for Informatics and Mathematics (ERCIM) headquartered in France and Keio University in Japan. Services provided by the Consortium include: a repository of information about the World Wide Web for developers and users, and various prototype and sample applications to demonstrate use of new technology. To date, nearly 400 organizations are Members of the Consortium. For more information see


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Testimonials for W3C's Recommendations - VoiceXML 2.0 and Speech Recognition Grammar Specification (SRGS)

Aspect Communications | Comverse | Genesys Telecommunications Laboratories | HP | IBM | Loquendo | Microsoft Corporation | Motorola | Nuance | Openstream, Inc. | ScanSoft | TellMe | Vocalocity | VoiceGenie | Voxeo | Voxpilot

Aspect Communications

Aspect Communications is committed to open, standards-based contact center solutions. We believe VoiceXML 2.0 can contribute to the renewed market interest in Interactive Voice Response solutions and speech applications. By integrating VoiceXML 2.0 into both its traditional and next-generation IVR platforms, Aspect is offering its customers increased flexibility, portability, and investment protection.

-- James Barnett, Chief Architect, Customer Self-Service Products, Aspect Communications

Comverse Americas

As a key participant on the W3C Voice Browser Working Group and a longtime supporter of open standards, Comverse is pleased to contribute to and endorse VoiceXML 2.0 and the Speech Recognition Grammar Specification as W3C Recommendations. The ratification of these standards allows Comverse to quickly and simply interchange speech recognition technologies in order to provide its customers with the best language recognition performance in each of the 100+ countries in which it does business. Comverse's vision for total communication is a borderless world where people are free to communicate in the way that is most appropriate and convenient for them. VoiceXML 2.0 and SRGS are major steps forward in realizing this goal.

-- Andy Wulff, Chief Technology Officer, Comverse Americas

Genesys Telecommunications Laboratories

Genesys is a long time supporter of VoiceXML, and is delighted that VoiceXML 2.0 has reached W3C recommendation status. As the world leader in open standards-based voice platforms, Genesys is committed to support VoiceXML and believes that open standards are the future for telephony and speech applications. This milestone is a key measurement in continuing the industry's evolution toward open standards-based technologies. Genesys looks forward to continuing its support of future advances in VoiceXML.

-- Paul Segre, Chief Technology Officer, Genesys Telecommunications Laboratories, Inc.


HP congratulates the W3C Voice Browser Working Group and the interactive media industry on reaching the VoiceXML 2.0 Recommendation. The completion of the very first open standard for voice services is a significant milestone in the telecommunications as well as Internet industries. Network and service providers are moving away from cumbersome, proprietary technologies and relying more on modular, standards-based solutions for the speed and flexibility they need to serve customer demand. Through our OpenCall Media Platform, HP enables customers to reduce cost and simplify change using VoiceXML in a carrier-grade environment.

-- Ed Verney, Director of Interactive Media Platforms, HP


VoiceXML 2.0, which has been key in the growth of speech applications by providing a standards-based framework, allows businesses to deploy applications today that leverage existing development skills and resources. Because it allows speech deployments to be built over a standard web-application infrastructure, VoiceXML also provides a clear upgrade path as applications grow - unlike closed, proprietary languages. VoiceXML forms the foundation for IBM's voice middleware, including WebSphere Voice Server and WebSphere Voice Application Access. By committing to open standards, we provide a clear path to future upgrades that leverage existing skills, allowing enterprises to extend their infrastructure. This commitment, and the W3C's work, is driving us toward the next phase of speech interaction and in the near future, multimodality.

-- Igor Jablokov, Program Director, IBM Pervasive Computing, IBM


As a leading player in speech technologies and voice platforms, Loquendo believes that VoiceXML 2.0 and SRGS 1.0 Recommendations are an essential step forward in promoting the speech application market. Indeed, it will boost the speech market, by enabling service providers, content creators, operators and voice portals to deliver a much richer user experience.Loquendo high-quality, high-performance technologies and platforms power over 2,000,000 calls every day in the telecommunications and enterprise markets throughout the world and guarantee solutions in 15 languages. Loquendo is very pleased to contribute to the development of this specification, and will continue to give a strong support to W3C and VoiceXML Forum activities.

-- Daniele Sereno, Vice President Product Engineering, Loquendo

Microsoft Corporation

W3C Speech Interface Framework is crucial to Microsoft's vision of making speech mainstream. We have implemented SRGS, SSML and SI into Microsoft Speech Server 2004 that integrates speech into HTML through SALT. Such a seamless integration with HTML has enabled our customers to extend their existing investments from desktop to multimodal and telephony voice access in a single, cost effective step. Microsoft Speech Server also provides development tools in the popular Visual Studio .NET environment, paving the way for Speech Interface Framework to be adopted by the mainstream Web developers. Today's recommendation on SRGS is indeed an exciting first step.

-- Xuedong Huang, General Manager, Speech Technologies Group, Microsoft Corporation

Motorola Labs

Motorola strongly supports VoiceXML 2.0 and commends the W3C Voice Browser Working Group for its efforts in developing this specification and bringing it to Recommendation status. VoiceXML greatly simplifies the process of creating and deploying voice services and is undergoing broad adoption across the industry for a wide range of applications. In the future, VoiceXML will provide the basis of multimodal-enabled services, combining the benefits of voice with visual and pen/stylus-based interaction to further simply and enrich information services delivered to wireless devices.

-- Mark Randolph, Director of Technology Planning and Commercialization, Motorola Labs


Since hundreds of our customers have already deployed speech solutions using VoiceXML, Nuance appreciates its ability to make speech application development simpler and less costly. We are very pleased with the World Wide Web Consortium's (W3C) decision to advance VoiceXML 2.0 to official recommendation status. The standardization of VoiceXML 2.0 will meet a real market need for open speech standards and accelerate the adoption of speech technologies worldwide.

-- John Shea, Vice President of Product Marketing and Management, Nuance

Openstream Inc

Openstream offers multimodal solutions based on its carrier-grade Smart Messaging Platform. The Platform implements both VoiceXML 2.0 as well as the XHTML+VoiceXML (X+V) to support multimodal interaction. Openstream believes VoiceXML is an important standard and is proud to be part of the W3C-led effort to ensure the standard can be implemented ultimately in real world multimodal solutions.

-- Raj Tumuluri, President, Openstream Inc


ScanSoft congratulates the W3C Voice Browser Working Group on reaching the Recommendation milestone for VoiceXML 2.0. It is clear that these developing standards are integral to the development of advanced technologies that change the way we communicate, from interactive voice response solutions to in-vehicle automotive applications. Businesses and consumers alike will benefit from the VoiceXML-based speech-enabled applications. ScanSoft is committed to VoiceXML and the W3C processes for standardization. Our SpeechWorks Family of ASR, TTS, and dialog solutions are uniquely optimized to support VoiceXML 2.0 and enable our partners to deliver industry-leading platforms, solutions,and services that are revolutionizing the business of speech.

-- Steve Chambers, Senior Vice President and General Manager Network, Speech Solutions, ScanSoft


VoiceXML 2.0, built on the Web foundation of HTML and JavaScript, is rapidly transforming the proprietary telephone network to an open architecture. While just having reached recommendation status today, more than 1 in 10 people in the United States have already called a VoiceXML application; by next year the number will increase to 1 in 4. As the universal mark-up language for the phone, VoiceXML uses Web data and voice recognition to deliver personalization to callers, low-cost phone sites for enterprises and new services for consumers. The combination of voice-over-IP and VoiceXML will unleash the creativity and pace of the Web to transform the telecommunications industry to an entirely open standards-based network.

-- Brad Porter, Director of Engineering, Tellme Networks Co-Editor, VoiceXML 2.0


Five years ago, we launched the VoiceXML Forum with the goals of making voice applications easier to develop and less expensive to deploy by leveraging existing internet standards and infrastructure. Today, as VoiceXML 2.0 becomes a W3C Recommendation, we see widespread adoption of the new standard, sparking a level of innovation in applications never before seen in telephony. At Vocalocity, we have designed and deployed a highly customizable and extensible software platform that would not have been possible without standards like VoiceXML 2.0. As a result, our OEM and System Integrator customers enjoy lower costs and more efficient use of their resources.

-- Ken Rehor, Chief Architect, Vocalocity; Co-Editor, VoiceXML 2.0; and Member of Founding Team, VoiceXML Forum

VoiceGenie Technologies

VoiceGenie Technologies is delighted that the VoiceXML 2.0 Specification has achieved full W3C Recommendation status, and applauds the diligence of the contributors to this effort. As a participant in the W3C Voice Browser and MultimodalcInteraction Working Groups, and as a board member of the VoiceXML Forum, VoiceGenie remains strongly commited to the support of open standards such as VoiceXML 2.0, SRGS and SSML. The VoiceGenie framework provides complete support for VoiceXML 2.0 and integrates a selection of industry-leading ASR and TTS resources. World-class customers including AT&T, Verizon, Oracle, Scotiabank and hundreds of others have selected the VoiceGenie framework for critical applications including customer care, directory assistance automation, retail services, voice activated dialing and more. VoiceGenie fully supports the work of the W3C and the VoiceXML Forum, and looks forward to continued rapid growth in the deployment of applications based on the open standards delivered to industry by< the W3C.

-- Stuart Berkowitz, President and CEO, VoiceGenie Technologies.

Voxeo Corporation

The release of the W3C VoiceXML 2.0 specification is another significant milestone in the explosive growth of VoiceXML. Prior to VoiceXML, Interactive Voice Response (IVR) platforms were proprietary IT islands - disconnected from mainstream IT infrastructure. VoiceXML and the W3C CCXML standard efforts bring IVR into the world of modern, integrated IT solutions. As a result of this progress, over 200 enterprise customers have already replaced proprietary IVR platforms with Voxeo VoiceCenter VoiceXML and CCXML platforms and hosting services.

-- Jonathan Taylor, President and CEO, Voxeo Corporation

Voxpilot Ltd.

Voxpilot is delighted that the VoiceXML 2.0 specification has reached W3C Recommendation, thereby establishing it as the industry standard language for the delivery of Web-based content and applications via the world's telephones. VoiceXML 2.0 is a key technology in Voxpilot's product suite. By integrating the Voxpilot VoiceXML browser, any telephony or media platform can be enhanced to support an open standard Web model for IVR delivery. The Voxpilot Telecom Solution enables any operator to become a voice service provider, as proved recently by Swisscom and Monaco Telecom. As an active member of the W3C Voice Browser Working Group, Voxpilot has made a significant contribution to the standardization of VoiceXML and continues its support for future evolutions of the specification.

-- Dr. Dave Burke, CTO, Voxpilot Ltd.

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