[Asterisk-Users] Amount of time asterisk take to pickup incoming call on ZAP interface

[Gilad Ben-Yossef]

Sophus wrote:
> Hello,
> 
> Ok...
> 
> After trying all this stuff, what still confuses me is -
> 
> I dial the zap interface --
> 
> Asterisk instantly says-
> --Starting simple switch on 'Zap/1-1'
> then a couple of seconds later
> Nov 4 19:11:39 NOTICE[1146895]: chan_zap.c:5356 ss_thread: Got event 2
> (Ring/Answered)...
> then another couple of seconds later
> Nov 4 19:11:42 NOTICE[1146895]: chan_zap.c:5356 ss_thread: Got event 2
> (Ring/Answered)...
> then another couple of seconds later
> -- Executing Answer("Zap/1-1", "") in new stack
> 
> why all the delay in executing the answer?

Because teh way caller ID information is passed of analog lines is by 
sending FSK modulated beep between the first and the second ring.

Therefore, what Asterisk does (if you asked to enable caller ID) is to 
register the first ring, get the the FSK modulated beep, wait for the 
second beep (thus knowing it is over) and then answering the phone.

Cheers,
Gilad


-- 
Gilad Ben-Yossef <gilad at codefidence.com>
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