[Asterisk-Users] Anyone having trouble with VoicePulse Connect?

[Martijn van Oosterhout]

On Thu, Feb 17, 2005 at 06:32:52PM -0800, beonice wrote:
> To answer my own question, at least partially, here is
> a quote from the Asterisk Configuration chapter in
> Paul Mahler's book "VoIP Telephony With Asterisk":
> 
> Table 1. Reserved Extension Names
> ----------------------------------------------
> Character   Name    Usage
> ---------   -----   ------
>   s         Start   A call that does not have
>                     digits associated with it,
>                     for example a loopstart
>                     analog line, begins at the
>                     "s" extension
> 
> Interesting. I don't understand it fully, but I'm sure
> I will if I stare at it long enough. :) I guess it
> implies that calls coming from DIDs have digits
> associated with them.

Correct. On ISDN lines, E1, T1 and related digital protocols, details
such as CallerID, Dialled Number, CLI Presentation, etc are passed as
part of the call setup, before there is any discussion of "ringing". So
Asterisk can go straight into the part of the script that matches.

However, on an analog line, you start with ringing and you still know
nothing about the call. CallerID comes later and Dialled number is
generally never sent at all. So you always start in "s".

Hope this helps,
-- 
Martijn van Oosterhout