- System architecture =======================
Ducklings is a positioning and navigation application with community service. The user creates an account and can add friends and foes which can then be seen on the map. The application can navigate the user to a friend while avoiding foes. During navigation the route is actively calculated according to the movements of foes and the target friend in order to always avoid the foes and give current navigation information.
The application requires system modules for positioning, navigation and authentication. The most basic function of the application is to show the user's and his or hers friends and foes locations on a map. Also most actions of the application heavily rely on this fundamental functionality. Because of the importance of positioning within the system it should be considered a main module.
Navigation is provided to find friends within the building while avoiding foes. Again this is a relatively important feature of the application and it should be considered a main module which is dependant on the positioning module. User positions are needed for any navigation to be accomplished. In this case the position of foes affects the navigation route, since foes should always be avoided. This active navigation is dependant on the movement of both the friends the user is trying to get to and the foes he or she is trying to avoid. A new route is calculated if a foe disturbs the current route.
In order to keep track of users an authentication module is necessary. It is essential for distinguishing users from each other and providing the right stored data to the client such as the friend and foe lists. The positioning system needs information about the user to provide other users the information who is in a certain position on the map, a friend or a foe. Furthermore only people within friends or foes are shown and this distinction is crucial.