Building Applications Frequently Asked Questions
This FAQ contains answers to questions about building VoiceXML applications using Tellme
- What's the purpose of VoiceXML?
- What's the history of VoiceXML?
- Are VoiceXML and VXML the same thing?
- Is VoiceXML an open industry standard?
- What version of VoiceXML does Tellme support?
- What is Tellme's role in evolving the VoiceXML as a standard?
- What is Tellme's philosophy regarding open standards?
- Where can I get additional information on VoiceXML?
Q: What's the purpose of VoiceXML?|
A: From the VoiceXML 1.0 Specification:
VoiceXML's main goal is to bring the full power of Web development and content delivery to voice
response applications, and to free the authors of such applications from low-level programming and resource
management. It enables integration of voice services with data services using the familiar client-server
In other words, VoiceXML provides a way to build a voice application that doesn't rely upon proprietary
techniques, but instead leverages the same well-known infrastructure used to build Web sites. This opens up the
world of voice applications to a wider audience of developers, and simplifies the integration of phone-based
interfaces with existing applications and Web infrastructures.
Q: What type of language is VoiceXML?|
A: VoiceXML is a declarative, XML-based language comprised of elements that describe the human-machine
interaction provided by a voice response system. This includes:
implement client-side logic.
- Output of audio files and synthesized speech (text-to-speech).
- Recognition of spoken and DTMF input.
- Control of telephony features such as call transfer and disconnect.
- Direction of the call flow based on user input
Q: What's the history of VoiceXML?|
A: The VoiceXML language is a product of the VoiceXML Forum, an industry consortium led by AT&T, IBM,
Lucent and Motorola. The Forum was created to develop and promote the standards necessary to jump-start the
growth of speech-enabled Internet applications. In August 1999, the forum released version 0.9 of the VoiceXML
specification. The final 1.0 specification was released in March 2000 after industry review and comment.
Though the VoiceXML forum was led by industry heavyweights, it needed to make VoiceXML an official standard to
guarantee the widespread industry support that would make VoiceXML a success. In May 2000, the Forum submitted
the VoiceXML 1.0 specification to the W3C, where it was accepted by the Voice Browser working group as the basis
for developing a standard language for interactive voice response applications.
VoiceXML 2.0 became a Full W3C Recommendation in March of 2005.
VoiceXML 2.1 became a W3C Candidate Recommendation in June of 2005.
At the time of this writing VoiceXML 2.1 is only two small steps away from becoming a Full W3C Recommendation.
Q: Are VoiceXML and VXML the same thing?|
A: Yes. "VoiceXML" is the official name of the specification. "VXML" is a commonly used
Q: Is VoiceXML an open industry standard?|
A: The VoiceXML 1.0 specification has not yet been officially ordained by the W3C as a "standard", but it's
the only such language that is both undergoing standardization and that has widespread industry support. In
addition to the four founding partners, the VoiceXML forum and the VoiceXML specification is supported by almost
200 companies including 3Com, Ericcson, France Telecom, General Magic, Hewlett Packard, Interactive Telesis,
Nortel, Oracle, Siemens, Speechworks International and of course, Tellme.
In fact, multiple companies have already developed, or are committed to developing, VoiceXML-based platforms.
These include Microsoft Tellme, Nuance, Speechworks, IBM, Motorola and Lucent.
Q: What version of VoiceXML does Tellme support?|
The Tellme Voice Browser supports both the
VoiceXML 2.0 and
VoiceXML 2.1 specifications.
Q: What is Tellme's role in evolving the VoiceXML as a standard?|
A: The W3C has accepted VoiceXML 1.0 as a note, and is using it as the basis for defining a Speech Dialog
Markup Language. Tellme has been accepted as a member of the W3C's Voice Browser working group, and has several
people actively working in several sub-groups, including the Speech Dialog Markup Language, Grammar and Speech
Synthesis sub-groups. Tellme participates in the weekly Voice Browser conference call and may soon take on
specification-drafting/editing roles as well.
Tellme was recently selected to be one of the six Editors co-authoring the VoiceXML specification in the W3C.
Tellme is also an active, supporting member of the VoiceXML Forum and participated in the last VoiceXML Forum
meeting held during Spring Internet World in April 2000.
Tellme is committed to implementing VoiceXML, while helping to drive its evolution based on implementation and
real-world experience. By extending the language to meet the needs of the development community and working with
the W3C and VoiceXML Forum to have those extensions adopted in a vendor-independent fashion, Tellme will advance
the state-of-the-art in voice application development while maintaining cross-vendor compatibility.
Q: What is Tellme's philosophy regarding open standards?|
A: Tellme believes that customers are tired of proprietary solutions and is committed to providing
best-of-breed technology through open standard protocols and interfaces. This includes not just VoiceXML, but
Not only is Tellme building products that comply with appropriate industry standards, but Tellme is also a leader
in the voice application space and is driving these standards based on its experience building and running the
first, commercial service based on VoiceXML.
Q: How do you handle speakers with foreign accents?|
A: Tellme's work on
, which naturally is designed to be usable by the widest range of speakers, has shown that the Microsoft speech
recognition engine employed by the Tellme Platform does a very good job with callers with strong foreign