Hello,

datalogger S3120 can be connected by "GSM adapter" to GSM modem (now we support Wavecom FASTRACK M1306B modem, Siemens TC65 support will be available soon). Communication is based on CSD (Circuit Switched Data) - i.e. you have one modem at PC and second remote modem at datalogger, program dials number of remote modem and data connection is established. You must use "optional" version of Program for dataloggers (not basic freeware version).

In a few weeks  GPRS communication based on Siemens TC65 modem will be available.

You don't necessarily need two MP009/2 (Data cable PC-modem), but it may be useful when there are some complications with data connection between two modems (you can connect both modems to one computer or two computers in office and debug communication). Also LP006 is needed only for modem at datalogger side. You must assure that your SIM cards have CSD dataservice enabled.

GSM is very similar with PC modems with telephone line. GPRS is newer method in data communication. In this method you can have public IP address. There are differences in price per kB. Price is country depend, for details please contact your local phone provider.

We have no experience with 3G nets and standards. But we plan discover information about 3G nets and offer solution in a several months.

About GSM, GPRS, 3G, WCDMA and other standards you can see on http://wikipedia.org e.g.