The key here is not holding the call past the authentication transaction. This is a relatively trivial javascript/lua application in freeswitch and the FS instances in this case are an excellent candidate for being containerized. Take the call, auth it with a voice captcha, then get rid of it. Perhaps do the auth during early media then 302 it. Your CPU cycles spent goes down by orders of magnitude this way. I know if at least one large provider doing exactly this on behalf of their customers. Imminently do-able. If you are interested in doing this, but timid, feel free to reach out off-list. Im happy to point you in the right direction. On 5/16/2017 2:01 PM, Alex Balashov wrote:
A "voice CAPTCHA" is a viable solution. But it does require infrastructure commitments on your part, even if, as you say, an Asterisk box can handle many concurrent calls. If you want to recycle that across multiple customers, that kind of moat can get mildly complicated.
The only concern I would have is from a user experience point of view; your customer might not want their callers to have to go through a confusing menu, and it would doubtless be psychologically off-putting. I don't know what kind of business the customer is, but imagine if you called your dentist's office and were prompted to enter some sort of PIN. As a layperson, you might think something is wrong with the phone system.