Yes, that's not a problem actually. You can do this on the modem itself or through the carrier by requesting a data only plan with no voice. Really, you shouldn't have to do anything, you'd need to have an application running on the server side to listen for and answer any inbound calls. I poked around a bit on the expanded AT commands list http://www.multitech.com/DOCUMENTS/Collateral/manuals/S000294K.pdf

I'd check autoanswer, first issue it "ATS0?", the number it returns is how many rings (1 - 255) before the modem picks up. If it's not 0, then you can set it with "ATS0=0", this disables autoanswer.
You can try to see if "AT+CPOF" will leave data connections going, it sends the phone offline. Further down in the document, it shows where you can send the data offline, so the above might be right - though it might also send the whole thing offline.

Tell you what, I sent an email to my contact at MultiTech asking him this question, I'll see what he has to say - there's far too many AT commands for me to figure out the right one!
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Jeremy D Pavleck
http://www.Pavleck.NET - OpsMgr, Powershell, monitoring and more!
http://www.Pavleck.COM - Random stuff. Probably not even up.
http://OpsMgr.Wik.Is - The Operations Manager Wiki!

"The fastest way to succeed is to look as if you`re playing by somebody else`s rules, while quietly playing by your own."
--Michael Korda
Sent from Minneapolis, Minnesota, United States

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