[asterisk-users] Disconnection supervision: what about PBX

[Stephen Bosch]

Stephen Bosch wrote:
> 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 :)

...and by that I mean ISDN BRI ;)

-Stephen-