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[max.bridgewater at gma...]

Hey Guys,

Pleas help me answer the following question. Sorry for being a bit off-topic.  I have a GSM-VoiP modem with just 4 SIM Cards. Is there a known mechanism that allows me to use this modem for more than 4 (albeit not at the same time) GSM numbers?  Let's say the phone numbers of the SIM cards inserted in the modem are call real phone numbers. My goal is to have some 10 additional virtual phone numbers served by this very same modem.

One way i thought this could be done is by forwarding the virtual phone numbers the 4 real phone numbers. Then, when somebody calls one of the virtual numbers, the Telco will forward it to the real phone number and it will end on Freeswitch box. My only problem is now that on the Freeswitch box I have no idea what virtual phone number was actually dialed. Any idea how to recover this phone number? I looked at the GSM specification and couldn't find a way.

PS. Purchasing DIDs won't solve my underlying problem.

Thanks,
Max.

[max.bridgewater at gma...]

Thanks Dave. I'm essentially trying to build a service in one country where there is no DID provider. If DIDs were available for such countries, that would have done the job.

Using the two-numbers-per-SIM approach  would help significantly, if I could only figure out, how to detect the Called Number using AT commands or Unsolicited Result codes. I was hoping the CLIP code could give me this information, but I'm still struggling to if it does or not. Any idea?

Max.

On Sun, Oct 18, 2009 at 12:04 PM, David Knell <dave@3c.co.uk (dave@3c.co.uk)> wrote: