I'll give you my two cents, if only to give you a good idea of what you can expect to uncover in your search for the holy grail of answer machine detection systems. And as one of your competitors in this space I cannot give away too many trade secrets :)
Alex is right on the money, there is no best, or single, answer machine detection process for asterisk based systems. AMD will only get you so far. In fact, you'll find you'll need a combination of custom processes, each one increasing the detection rate by a small %. There is a white paper somewhere outlining issues with answer machine detection (if I find it I'll send the URL) and even the research done in that paper which tested some of the more advanced industry detection applications gave an overall 70% accuracy in detecting machines. I can tell you that we employ a combination of customer AMD modules, carrier detection, wireless detection, SOX silence stripping, BackgroundDetect, DTMF and more just for our machine detection process. It also took us two years to perfect it and yet every week we get the "my message isn't being left on my voicemail" support issues. So as you can see the answer is not a single process but a combination of processes that improves your overall detection rate. Hope this helps. Alan www.group2call.com --- On Tue, 10/7/08, Alex Balashov <[EMAIL PROTECTED]> wrote: From: Alex Balashov <[EMAIL PROTECTED]> Subject: Re: [asterisk-biz] Custom AMD Module for Improved Answering Machine Detection Needed To: "Commercial and Business-Oriented Asterisk Discussion" <[email protected]> Date: Tuesday, October 7, 2008, 9:56 PM The best off-the-shelf solution I've seen for this comes from Paraxip in the form of their NetBorder CPA (Call Progress Analysis) product. They use a B2BUA that you can send calls through out of Asterisk, and which will return a certain code as a custom SIP header depending on the disposition. "The best" still isn't saying much. You're going to get many of the same problems as you get with AMD. The marginal improved accuracy may or may not be worth the cost. That's just how it is. This is impossible to do right in a way that is applicable to the variance of environmental and acoustic situations - as you mention, works with one carrier and not with another, and other variables. Most likely, developing such a thing would be a pointless waste of time and energy because to get beyond a certain rate of accuracy is to ask for a perpetual motion machine. Just my $.02, of course. Chris wrote: > We're looking for a company (preferably U.S. based) that can help us > with the development of a custom module for advanced Answering Machine > Detection. We need to be able to properly detect a live answer vs. an > answering machine or voicemail (including cell phone ringbacks, etc.) as > well as wait for the beep to leave a message. We've tried tweaking the > built-in AMD settings for Asterisk, but all this accomplishes is > improving detection rate for one carrier and eliminating it for > another. We're looking for a company that has worked on similar > projects before that could help us with a potential solution. Thanks in > advance! > > _______________________________________________ > --Bandwidth and Colocation Provided by http://www.api-digital.com-- > > AstriCon 2008 - September 22 - 25 Phoenix, Arizona > Register Now: http://www.astricon.net > > asterisk-biz mailing list > To UNSUBSCRIBE or update options visit: > http://lists.digium.com/mailman/listinfo/asterisk-biz -- Alex Balashov Evariste Systems Web : http://www.evaristesys.com/ Tel : (+1) (678) 954-0670 Direct : (+1) (678) 954-0671 Mobile : (+1) (706) 338-8599 _______________________________________________ --Bandwidth and Colocation Provided by http://www.api-digital.com-- AstriCon 2008 - September 22 - 25 Phoenix, Arizona Register Now: http://www.astricon.net asterisk-biz mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-biz
_______________________________________________ --Bandwidth and Colocation Provided by http://www.api-digital.com-- AstriCon 2008 - September 22 - 25 Phoenix, Arizona Register Now: http://www.astricon.net asterisk-biz mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-biz
