GPS (Global Positioning System) is a useful technology for human being. Such as for navigation, Geographical Information System(GIS), Military purposes, earthquake monitor system, and Automated Vehicle Location. The Automated Vehicle Location(AVL) enable a user to track the vehicle position in real time.
The simple illustration of the AVL is shown below
There is a device added to the tracked vehicle. This device contain 2 chips. One chips for receive position data from the satelites, one other send the position data to the application server over the PLMN Network. Usually the position data send by GPRS, or SMS. The positioning data are processed by application server to a webpage. So we can know the vehicle position by open the webpage from another device that connected to the internet.