CCXML: insufficient VoiceXML integration details?

Hello www-voice,

Section D.9 of the CCXML 
spec(http://www.w3.org/TR/2010/CR-ccxml-20100401/#VoiceXMLIntegration)
attempts to describe how to integrate support for VoiceXML's<transfer> 
within CCXML.

It appears incomplete in the following regards:

1) no clear way for VoiceXML to compute the "duration" shadow variable
   of the <transfer> tag. Only CCXML knows how long the far side was 
connected.

2) no way for VoiceXML to indicate whether caller should <join> to the 
callee
   to hear call progress tones before the call is answered. If there is no
   transferaudio attribute of the <transfer> tag, there is no harm in an 
early
<join>. However, if transferaudio exists and that <join> occurs the caller
   will never hear it.

3) no way for VoiceXML to abort playback of any transferaudio once the 
callee
   answers. A case can be made that because CCXML controls the switching the
   connections can be made such that the output of the playback doesn't 
go anywhere
   but this is inefficient.

4) no way for VoiceXML to indicate to CCXML that transferaudio playback 
has completed.
    Such notification would allow CCXML to then <join> caller and callee 
to allow
    caller to hear call progress (please wait while we connect your 
call....ring ring ).

I propose a new event - dialog.transfer.connected - to inform VoiceXML
the far side has answered. This will solve #3 above and allow VoiceXML 
to start
its own timer for duration also solving #1 (time difference calculated 
when VoiceXML is told
end of transfer).

Finally, a new dialog.transfer.callprogress event would signal CCXML to 
peform an
early <join> of caller to callee for call progress before the call is 
answered.
VoiceXML could send this right after the dialog.transfer if there is no 
transferaudio,
or after transferaudio completes if there is transferaudio. This would 
solve #2 and #4 above.

Regards,
Chris

-- 
Chris Davis
Interact Incorporated R&D
512-354-8202

Received on Thursday, 2 December 2010 14:05:30 UTC