simple gps gsm sstem questions

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simple gps gsm question

hi all,

I'd like to know how the following gps/gsm module could function. It should be in a car, such that when ever the car moves into a "interest point", the gps module should alert in a certain way. Interest points are places on the central server which, when the gps module enters - it should alert. We would set the interest point co-ordinates ourselves.

This is how i think it would function

module made of:

- GPS module
- antenna connected to the gps module
- gsm module able to send gps co-ordinates every X time frame via gprs
- the module would need at least one output port in order to realise the alerts in either LED format or using beepers.

server consist of:

- ability to receive gps co-ordinates and compare against "interest points"
- ability to manually enter interest points co-ordinates
- ability to send alert back to gps module if an interest point is entered - it should also send the interest point code. i.e. interest point xyz

Questions......

- am i right?
- how to make it simpler/cheaper?
- any recommendation for cheap GPS gsm modules? Simcom ones seem to be - good, but too "good" - almost over engineered for this application, when all i want is to send raw co-ordinates back and forth and let the server do most of the work.
- any licensed/free servers? (i.e. gps-trace.com) which could be used?

thanks....