A generic query on Modems

[Ajay Garg <ajaygargnsit gmail com>]

Hi All.

I am sorry for posting on this list, as the subscription-pages(s) on the 3GPP-mailing-lists do not open (the server seems to be down).

Other than that, people on this list are the best experts with Modems :)

We are writing an application that would ultimately be hosted in embedded-environments (micro-controller interfaced with a GPRS-modem chipset), and we were wondering if it would be feasible to integrate the TCP/IP stack in our application, so that the application becomes modem-vendor-agnostic.

Thereafter, we would talk with external Web-Server using the following algorithm ::

1)

Create a connection between Modem with the APN, using *only* standard Hayes Command(s), mostly AT+CGDONT

2)

Thereafter, the modem would be switched (automatically) into data-mode.

3)

Create packets in our application, and wrap the TCP and IP headers within our application using the integrated TCP-IP stack (for eg. lwIP in our application.

4)

Create and use TCP-contexts, by sending/receiving the packets of step 3) while the modem remains in data-mode.

Is our approach worth the effort?
Are a good number of modems expected to behave fine by our algorithm? Or there is too much variety of modems, so much so that no single general algorithm would suffice ?

We will be grateful to listen to your experiences.

Thanks and Regards,

Ajay