Implementation Notes

This section contains additional details about how the Vocalocity Voice Browser handles the following areas:

u Bargein

u Default encoding

u DTMF-only applications

u Infinite loop detection

u Strict content type detection

u Time unit designations

u Using a file-based URL

For vendor-specific notes, see Chapter 4, Telephony and Speech Notes.

Bargein

Support for speech-based bargein is supported. Hotword or recognition-based bargein is not currently supported.

Default Encoding

The default encoding for all documents, if not specified, is UTF-8.

DTMF-Only Applications

By default, the Vocalocity Voice Browser assumes the input modes of "dtmf" and "voice." If your application is DTMF-only, you must specify the inputmodes browser property in your application:

If you do not specify the inputmodes property, the Vocalocity Voice Browser will attempt to perform speech recognition and will not be able to run your application.

Infinite Loop Detection

Infinite loops can be caused when an application or the platform throws an event which is caught and re-thrown recursively.

The Vocalocity Voice Browser will attempt to check event recursion depth and prevent an infinite loop in the application.

In the vocalos-node.xml file, set the VoiceXML property vocalos.event.maxcount to control the maximum number of times a single event is called from within the same execution context. The default count is 10. Upon reaching the max count, the application will be forced to exit. You can control the max count within your application by setting this property.

Strict Content Type Processing

You can turn on strict content type processing by setting the Java system property vocalos.vxml.strict.contenttype.mode to "true." (The default value is false.)

If you enable strict content type processing, the Vocalocity Voice Browser requires the Content-Type HTTP header in all documents returned from the web server to be application/voicexml+xml. Documents without this content-type will be rejected as invalid VoiceXML documents.

Time Unit Designations

Time unit designations for default browser properties can be specified in milliseconds. (For a list of these properties, see Vocalocity Property Defaults.)

In Vocalocity Version 2.3, the VoiceXML Interpreter does not require a designator in the value. However, this has been fixed in Version 2.4.1. You should specify the correct designator in your application to ensure conformance with the VoiceXML 2.0 standard.

Using a File-Based URL in Applications

To specify a file-based URL instead of HTTP, use the URL format:

The following example shows how you would set this in Windows: