How do I find the IP address of a GPRS modem?

Question

I want to pull data from a device that is accessed via a serial protocol and has a GPRS modem attached which should allow transparent access over an IP connection. It seems to me that this approach is upside down, because how should I know at which IP address the device currently is? Unfortunately, the device itself is rather dumb, so I can't make it send something to my server, which would reveal the current IP.

For home routers on dialup lines, there's dynamic DNS services. Is there something equivalent in the mobile world? Each modem would, of course, have its phone number as a reliable address, but how does that help me?

Practically all material on GPRS etc. that I can find online seems to be concerned with initiating the connection from the modem side, since that's what the system is designed for.

Answer 1

You're right, typically the GPRS device has to initiate the connection, since they are not usually assigned static IP addresses.

I would suggest looking again at the device, because it certainly should have a way of initiating a connection with a remote server (you will probably need to directly connect it to a PC to initially configure it). I've worked with quite a few different GPRS devices, and they all worked this way.