any audio CAPTCHA use in Voice Applications accessed by phone?

An ongoing accessibility problem has to do with robot harvesting of 
free services vs.
disability access to those services.

http://www.w3.org/TR/turingtest

One of the current strategies is to make optional CAPTCHA 
transactions available
that depend on different human functions: one you need to see, another you
need to hear, one you need to work logic puzzles, etc.

It would be helpful for the 'universal' interaction design if there 
were any audio-only
audio-CAPTCHA practice in the wild to benchmark.

Is anyone here aware of voice-enabled or other IVR applications that 
use a muddy
prompt to weed out robot callers?  Or is this unnecessary because the phone
call to access the IVR in the first place is enough of a barrier 
compared with a
TCP/IP connection?  Or it's useless because of the prevalence of good speech
recognition in this domain?

Al

PS:  Compare with the discussions of the under-development reCAPTCHA audio
CAPTCHA.

http://tinyurl.com/ywyqs2

Received on Saturday, 14 July 2007 15:20:25 UTC