Gprs modem ip address

[srinivas_n0011]

i am using some number of gprs modems its assigned with dynamic ip,my modem need to send data to the server,my problem is how to identify the which modem has sended data to the server.
pls help me

 

[louisnells]

This can be handled in multiple ways. Say you are using GPRS modems from different service providers. Each service provider is assigned with unique range of IP addresses. Hence even though you are getting IP assigned dynamically, these IP address will have a master set of IP ranges and you can get match the modem IP address with the ISP range and figure out the modem in use. There are even some free databases about these IP ranges e.g. MaxMind - GeoLite Country | Open Source IP Address to Country Database or you can use some free services for the same functionality MaxMind - Resources for Developers

Say you are using same service provider on all modems. You could still encapsulate modem identity info in the data sent to the server and match the modem from this info. Say you are using HTTPS for communication with the server, you can put modem identity info as part of the SSL certificate on the modem and later decode this data in the HTTPS server application running on the server machine.