[Asterisk-Users] Seize phone line

[Rich Adamson]

Joe Pukepail wrote:
> I have a question, we have some locations were I'm just planning on 
> putting in a PRI, management also wants analog lines incase the PRI is 
> down and someone calls 911.  Is there a way to use asterisk to seize a 
> phone line from the fax machine? 

Multiple ways to do that. Something like the SPA3000 provides both an 
analog pstn interface and fxs interface (for the fax machine), and both 
of those interfaces are addressable via asterisk's dialplan. Or, use the 
sangoma A200D card with an fxo and fxs interface and you'll get the same 
functions (but with better quality).

>  I don't want to have to have an analog line that only gets used in the 
> very rare situation with the PRI being down and someone needed to dial 
> 911 (other incoming and outgoing calls would be routed over a private T1 
> to another location), but I don't want to just tap into the fax line 
> because there is a chance that someone could be sending or receiving a 
> fax at the same time.
>  
> I found this: http://www.twacomm.com/catalog/model_LSR-1.htm  on an 
> internet search, anyone have any experience with this (or something 
> similiar)?  Would it work with asterik?
>  
> On a related issue, at locations where we have 3 or 4 phone lines 
> connected to asterisk and they are all in use and someone dials 911 we 
> want it to disconnect one of the active calls so the 911 call can be 
> made.   Does anyone know how to do this?  Would I need to use a device 
> like the above or is there a way in software to do this?

Can't answer the above as it depends 100% on the exact equipment that 
you deploy to provide such services. Example, if you deployed the SPA300 
(assuming analog phones) and you had it configured so as incoming pstn 
calls were directly connected to the fxs phones, asterisk has no control 
over the spa3000 path and can not dump existing calls.