On July 31, 2002, the SALT Forum submitted the SALT specification
to the Voice Browser and Multimodal Interaction working groups of
the World Wide Web Consortium (W3C).
This new development and the benefits that SALT brings to the W3C
could alter the direction of the Voice Browser working group as well
as commercial support and developer support for SALT.
The SALT Forum was established by Microsoft to create an XML
language for developing multi-modal applications that can accept
speech, typed or written input on computers, telephones, PDAs,
wireless devices and tabletop PCs. The Voice Browser group has been
supporting the VoiceXML standard since it was submitted to the
working group in 2001 by the VoiceXML Consortium.
SALT provides a number of benefits to the Voice Browser working
group that the VoiceXML specification lacks.
First, the SALT specification is licensed royalty-free. While the
W3C has stipulated that standards must also be licensed
royalty-free, several contributors to the VoiceXML specification–including IBM, Motorola, Avaya, Lucent, Mitsubishi, Nokia, Nortel,
Philips and Telera–have only agreed to license their intellectual
property under Reasonable And Non-Discriminatory (RAND) terms, which
means that VoiceXML cannot become a Web standard in its current
Now that SALT has been officially submitted to the W3C, the W3C
could decide to offer up SALT as the voice browser standard instead
of VoiceXML. This, of course, doesn’t prevent companies who are not
part of the SALT Forum from perusing patent claims that may also
pertain to the the SALT specification.
Secondly, SALT is an extension of HTML and enables developers to create
multi-modal applications. VoiceXML doesn’t possess any multi-modal
capabilities, however, IBM, Motorola and Opera jointly proposed
what they call, "XHTML + Voice." The proposal dictates
that VoiceXML would be re-formulated as a collection of XHTML
modules, which could then be imported into an XHTML document,
thereby providing the capability to incorporate spoken and visual
While the proposal solves the multi-modal requirement,
it also suffers from intellectual property encumbrances which would
prevent this proposal from being implemented by the W3C. The Voice Browser group, however, could decide to incorporate the SALT
multi-modal features while keeping other aspects of VoiceXML intact.
Third, while the first version of the specification was only
recently introduced in 2002 and the SALT Forum was just formed in
2001, its membership has grown to include companies such as Siemens,
Voice Genie, Intel, InterVoiceBrite, Genesys, Edify, Compaq, Verizon
and Korea Telecom. The accelerated interest in the commercial
application of the SALT specification indicates that at the very
least, many of these companies will be offering SALT support in
addition to VoiceXML. At worst, some companies may choose to support
SALT instead of VoiceXML.
So what happens now? According to Jim Larson, chair of the Voice
Browser working group at the W3C, the group is reviewing the SALT
submission in addition to a previously submitted proposal from IBM,
Motorola and Opera for multi-modal interaction.
It’s not yet clear what the impact of this development will be
for VoiceXML. The Voice Browser group may incorporate parts of SALT
that are lacking in VoiceXML. Heck, there’s even a remote
possibility that the group will adopt the entire SALT specification.
The impact for SALT will be more obvious. SALT is taking a more
Web developer-centric approach and will therefore attract more Web developers
who want to incorporate speech into their Web applications. The
submission to the W3C will provide more visibility for the standard.
SALT applications will begin popping up in the next 12-18 months as
vendors start adding SALT support. Microsoft, for one, is planning
on integrating SALT into its developer tools and servers. According
to James Mastan, director of
marketing for the .NET Speech Technologies Group at Microsoft, "the key point for Microsoft is that an open industry standard emerges that is royalty-free and which accommodates both telephony and multimodal speech-enabled Web applications in a manner in which the millions of existing web developers that are out there can comfortably integrate speech into their Web
Microsoft has recently released a Beta version of their .Net
Speech SDK, which showcases a very promising SALT development environment
and integrates into Visual Studio .NET.
Browser Patent Statements
- SALT Forum
- W3C Voice Browser Activity
- W3C Multimodal Interaction Activity
- XHTML + Voice
.Net Speech SDK order form
About Jonathan Eisenzopf
Jonathan is a member of the Ferrum Group, LLC which specializes in Voice Web consulting and training. Feel free to send an email to [email protected]
regarding questions or comments about this or any article.