[asterisk-users] b option in Directory

[Jared Smith]

On Wed, 2009-12-02 at 09:40 -0600, Danny Nicholas wrote:
> There are indeed lots of improvements, but if the OP NEEDS some features
> that automagically worked in Zaptel that still don't in DAHDI (POTS Line
> supervision...) 

*Please* don't continue to bring up this example in the mailing lists.
>From everything I've been able to find in my research, there is *no
difference* in answer supervision (or far-end disconnect supervision,
for that matter) between Zaptel and DAHDI. 

I've explained this once before, but I'll explain it yet again so that
hopefully Google will index it for the next person that comes along and
asks it:

Let's assume I'm making an outbound call on an analog phone line
connected to an FXO port in my Asterisk system.  In the United States,
the telephone companies don't send any kind of signaling to let me know
that the far end has answered my call.  Hence the reason Asterisk treats
*all* outbound calls on FXO ports as having been answered, unless you go
changing settings in zapata.conf/chan_dahdi.conf (like setting
"answeronpolarityswitch=yes").  Obviously telephone signaling can and
does vary from country to country, which is why have settings like
"answeronpolarityswitch" and "hanguponpolariyswitch".

In short, there's no difference in Zaptel and DAHDI in this regard, so
please don't keep using it as an excuse for people to stick with Zaptel.
If in fact there were any regressions of this nature in the transition
from Zaptel to DAHDI, rest assured that we would have corrected them by
now.

--
Jared Smith
Digium, Inc.