[asterisk-users] Disconnection supervision: what about PBX

[Stephen Bosch]

Stephen Bosch wrote:
> Trevor G. Hammonds wrote:
>> Yuan,
>> Well engineered analogue PBXs typically do not use standard loop start
>> subscriber lines.  When digital trunks are not an option, they use analogue
>> PBX and/or DID trunks.  At the very least, ground start circuits are
>> preferred to avoid "glare".  The best call quality for analogue is achieved
>> by using four-wire E&M trunks that provide answer and disconnect
>> supervision.  There are two-wire trunks (which are probably more common), as
>> well as different signalling methods.  These trunks require special
>> interface hardware, and I am unaware of any that work with Asterisk.  As the
>> cards are typically very expensive, it is usually better to go with digital
>> if you require that functionality.  It would be nice to see a BRI interface
>> for Asterisk that works in North America, as BRI circuits are often
>> comparable in price to analogue lines.  
> 
> Are BRI circuits what phone companies call "digital" lines for use with
> digital sets, such as with digital Centrex?
> 
> I'm not aware that Telus even offers BRI.

Sorry -- BRI is ISDN, not digital Centrex.

I'm still not aware that Telus even offers ISDN anymore :)

-Stephen-