[Asterisk-Dev] Re: Answering Machine detection

[Nitin Joshi]

Hi,
Thanks to Matt and Steve for replying to my post :-) . Steve, I would really
like to know more about your code like how it exactly works and how resource
(cpu and memory) intensive it is.

Matt, following are the details you asked for:
I want my system to detect atleast 80% of the answering machines and that
too within 1-3 seconds, just like dialogic boards.
Otherwise there won't be much reason to replace the existing predictive
dialer system with Asterisk.
We're going to have 24 to 48 lines initially and it'll definitely be T1.
We've not yet finalised which cards (Digium, Sangoma or if possible
Dialogic) to use.
Also, we'll be writing our own Predictive dialer application which will talk
to Asterisk using its Manger API interface.

I would be really grateful if you could guide me on the above and also throw
some light on the following:
- Does Asterisk support the Dialogic D/480JCT-2T1 board (That's what our
current system is using) ?
- Which is the best T1 card for use with Asterisk?


 Message: 1
> Date: Fri, 9 Sep 2005 19:20:22 +0200 (SAST)
> From: steve at daviesfam.org
> Subject: Re: [Asterisk-Dev] Answering Machine detection
> To: astmattf at gmail.com, Asterisk Developers Mailing List
> <asterisk-dev at lists.digium.com>
> Message-ID: <Pine.LNX.4.58.0509091918450.8011 at bob.daviesfam.org>
> Content-Type: TEXT/PLAIN; charset=US-ASCII
>
>
>
> On Fri, 9 Sep 2005, Matt Florell wrote:
>
> > Answering Machine detection is very CPU intensive in Asterisk and will
very
> > much limit your capacity per server if you implement it. This is because
> > unlike expensive Dialogic boards, Digium cards do not have an array of
> > on-board DSPs to handle the signal processing needed to accomplish good
> > Answering Machine detection.
> >
> > What percentage of Answering Machine detection are you trying to
achieve?
> >
> > How much delay time is acceptable to you? Dialogic systems range from
1-3
> > seconds of delay while they process the signal to determine whether it
> > thinks there is a person on the other end.
> >
> > How many Lines do you think you are going to be able to have dialing
> > outbound with Answering Machine detection active?
> >
> > What kind of lines(trunks) will you be using this with? (T1/E1s, SIP,
> > IAX...)
> >
> > What predictive dialing software are you planning on using on Asterisk?
>
>
> Gee - my code for answering machine detection works within a second or two
> and simply works by listening for the "blah blah blah" of an answering
> machine as opposed to the shortish phrase and wait of a real person.  It
> manages about 90-95% correct detection.
>
> Does that rate as OK?  If so, I'll put it up on bugs.digium.com
>
> Steve
>