[asterisk-users] Credit Card processing machines

[Jeff LaCoursiere]

On Tue, 17 Feb 2009, Andrew Joakimsen wrote:

>>>
>>> Most alarm systems around here use bursts of dtmf - not an actual
>>> modem to communicate with alarm central.
>>>
>>> Yes I have seen these have many issues with voip in the path.
>>>
>>
>> You mean they communicate with an IVR?  Seems like that could be made
>> solid with the right DTMF options enabled on the ATA.
>>
>> FWIW that makes a lot more sense than a modem connection.
>>
>
> No, it's not an IVR. It's a protocol called ContactID.
>

Ahh.  I just read a PDF on the protocol.  It may as well be an IVR - it is 
all standard DTMF with normal DTMF timing between digits.  Where does VoIP 
introduce a problem?  Seems like this should work well.

j