That's what I don't understand John.  This analog signalling is common in 
the US as well. The old TASCOM PBX that we have was built in Chino, CA.  
Analog DID lines seem to be commonly supported on the old as well as new 
PBXs (for compatibility reasons). I think this was done because the PBX has 
considered an autonomous unit: self powered and self provisioned, hands 
off by the Telco.  The only reason I can think that Asterisk doesn't support 
the full version of DID directly is that no one has worked on drivers for the 
cards.  Brooktrout seems to have some.  This looks like a gaping hole to me.

The E&M Winkstart applies only to E1 digital connections. Sure DID is 
supported on Asterisk, but only in terms of the dialing protocol. Anyone else 
have any insight into this lack of support for the full DID trunk line 
circuits? 
Are we talking legacy here?  Is ISDN expected to fill the gap? If so, this cuts 
out support for small message service businesses (in some locales) that 
can't afford a T1/E1.  Of course, the digital deals are probably better in 
other 
markets.  Maybe T1s are less that $1K in the larger cities.

Thanks,
Peter M.

> On Wed, 2006-07-26 at 16:23 -0300, [EMAIL PROTECTED] wrote:
> > Perhaps some of you are not aware of how the old DID lines work.  When the 
> > incoming call 
> > is transferred to one of these trunks, 48 volts must be present. The CO 
> > switch seizes the 
> > line and polarity is reversed by the PBX to indicate ability to receive the 
> > call.  This is called 
> > wink start.  Four digits from the bank of DID numbers are then transferred 
> > and the call is 
> > connected.  It is a standard ability of a real PBX since it has been 
> > traditionally assumed that 
> > DID trunking can be handled by a PBX.  In fact, a lot of the new IP PBXs 
> > out there do this 
> > form of DID, also known as DID-over-analog.  A few of these lines are much 
> > cheaper to run 
> > than a T1.  That's why I'm disappointed that there doesn't seem to be any 
> > direct support for 
> > DID cards on Asterisk.  We have two sets of these trunk lines to support 
> > but it needs to 
> > function for the messaging service to start.
> 
> According to 
> http://www.voip-info.org/wiki/index.php?page=Asterisk+config+zapata.conf
> 
> Asterisk supports the following signalling types: 
>       * em: E & M Immediate Start
>       * em_w: E & M Wink Start
> ...
> 
> The description you gave above seems to be E & M Wink start.
> 
> I hadn't been aware of this type of signaling until you brought this up.
> Is it commonly available in Canada?
> 
> John

********************************************************
Peter MacFarlane, ACP
Network Administration &  Programming     
Target Call Center/ Message Centre P.E.I.  
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