Library to send SMS messages via IP connected device

Question

Hello, I'm looking for a library (win32) to be used in a Delphi project that will enable me to send and receive SMS (text messages) via GSM modem devices connected via Ethernet (listening on an IP address).

All the libraries I found until now support devices connected via COM/USB/bluetooth/InfraRed, but non of them support a direct connection via IP (using a COM to IP redirector or virtual COM port is not an option for us).

Does anyone know of such a library (or a good classic COM/USB/... AT command lib (GSM07.05 GSM07.07 compatible) that includes full source code so that we can extend it ourselves for straight sending of AT commands via telnet over IP)?

Thanks Koen.

Answer 1

I'm not aware of a library to do this, but you can checkout the source of Kannel. Their is a rawtcp or telent modem type that might help you.

Since AT commands are just text you should be able to have your program establish a TCP session and then issue the commands directly. The exact commands your modem uses may be manufacturer or even model specific, which may be why there are no libraries for this, but should be listed in the documentation.

Answer 2

I think the answer will be 'no'. I can't think of any GSM device that is added to a PC via IP, they're always serial comms, so really you're looking for a library that takes ethernet commands and writes them to the device as serial (effectively a wrapper). I doubt you'll find this, all such wrappers will be written to expose a higher-level programming language functionality (eg a C# class or a C lib), and the calls you make will be via that language constructs - not IP.

As a result, you'll be best off with a Serial->IP converter, they work remarkably well (we use them to connect a serial device to a computer over distances too long for serial cables) and they're completely transparent.