Has anyone successfully interfaced a ring-down circuit (AT&T) to a hosted VoIP provider? I have a Fire Dept that has a ring-down circuit that goes to 911 services. It operates in both directions. I am trying to find a solution (SIP gateway box??) that will allow me to replace/remove the SLT/POTs phones at the firehouse and integrate the VoIP phones with the fore mentioned RD circuit. I could see using a VoIP ATA for inbound calls from 911 services locale to the firehouse, but not for the other direction (firehouse to 911 services) because ATAs can't be programmed to auto answer (go off-hook) in order to trigger the ringdown call. Any ideas? Thanks - Mike

I suggest you leave it as is. It can't be much of a savings and this kind of stuff works best on a POTS line.

Only with a speed dial number

You can make an ATA dial a specific number, but you'd lose the direct-dial from the PSAP to the firehouse, unless you set something up to facilitate that. More equipment, more opportunities for things to fail; POTS lines magically still work when internet backbones take hits. The potential risk may not fly too well with EMS system. You're better off leaving it alone as John recommended