[asterisk-users] Detecting answer with an analogue card

[Andrew Kohlsmith]

On Monday 05 February 2007 8:26 am, Stefano Corsi wrote:
> Uhm... I still don't understand... Does call progress detection work
> fairly well for analog cards with the US telephony system, or it's
> still something experimental and randomly working? And if it's
> working in US, how difficult can it be to port it to the (for
> example) Italian system?

Put it this way: Any serious Asterisk install that wants to pass the wife test 
will have "progressinband" turned off in a fairly short order.

> As an alternative, what about having a device (let's say Inalp Patton
> gateways) connecting to the telco with ISDN and to Asterisk with
> ethernet/SIP. Should I get correct ANSWER detection (and thus correct
> billing CDR records) with this setup?

I think you're starting to reach beyond what's practical.  But yes, something 
like that would work just fine, because both ISDN BRI/PRI and SIP are digital 
protocols and employ the concept of line state beyond the simple "on 
hook/offhook".

-A.