Question : Receiving GPS Data via GPRS

Hi,
We currently run a vehicle tracking application that uses SMS to send vehicle locations to a modem attached to a server on which I run a small SMS receiving application which in turn inserts the SMS data into a table in our database.  I am trying to find information on how to do this via GPRS and I cant seem to find much information on this service on the web.

The only way I can think of being able to do this via GPRS is if the sending device can format its data somehow into an email which would be picked up by something like SQL Mail or similar.  Would it be possible to do this another way?
Im really at a loss trying to find out an easy way to do this, like our current SMS system.
Thanks
D.

Answer : Receiving GPS Data via GPRS

Well first and foremost, before you explore any technical issues, you need to look at the cost of GPRS. Do you already have GPRS included in your service plan? If not, are you aware that, if you choose a per-Kbyte plan, you'll be charged based on the size of data you're sending?

If you don't know exactly sizes per month or don't have a good handle on your exact size requirements, you could purchase an unlimited data xfer package (generally $80/mo), but that may be overkill for you if SMS is currently working well for you otherwise. If you don't care about the monthly service costs and are mainly considering moving to GPRS for reliability or capacity reasons, then it's a moot point but you still have to consider service cost as one of your design inputs.

Next, what type of modem are you using? Do you know whether the modem has a PPP stack embedded or not? If not, you'll need to find a PPP solution in order to get any TCP/IP going across your link. (SMS doesn't require this because it's a totally self-contained system within GPRS and imposes strict limitations, hence the name "short message".)  A PPP stack can be bought off-the-shelf from reputable companies like Treck, but these are not going to be cheap. You could also find a shareware version if you've got time and expertise to integrate it, and if your OS is supported.  

It sounds like you're doing some sort of embedded thing rather than a PocketPC or similar deal - is that correct? With your TCP/IP link established, there are many possibilities in PPC world and many APIs available to do whatever (HTTP or email). But in the embedded world, there are no easy answers to any of this - you'll probably be limited to the AT command set supported by your modem, and you'll be responsible for stack management too. To get of taste of this world have a look at the vendor website http://www.harvest.com/spe_debug.htm .

Let us know what you decide to do and what your preferred approach will be.

j.m.