What you get
The API allows you to write applications that can reach clients located in an area defined by the sender. This could be used, for example, to send warning messages to warn other motorists of a road hazard in the vicinity of the sender, or it could be used to send advertising messages from a shop owner to people entering the vicinity of the shop. The defined area may have arbitrary shapes and sizes (within limits). There is also the possibility for clients to send uplink messages.
How it Works
On server side, the API provides an interface to the Geo Messaging Server. This interface can be used to send arbitrary content in real-time to all registered Geo Messaging Clients that reside in the region you specify along with the message. This region can have the shape of a circle, an ellipse, a rectangle or any convex polygon.
On the client side, an API provides an interface that allows an application to receive Geo Messages. The underlying geocast architecture employs a grid-based geocast method. The position of a client is updated whenever it crosses the border of a virtual grid underlying the physical map/area the client is located in. The geocast server updates the clients with a local view on the virtual grid when necessary.
Different applications developed for this enabler use an individual service ID namespace to achieve multitenancy. The location information of clients is used by the Geo Location Messaging server only to route messages to the clients and is never exposed to any application.
In Intelligent Transport Systems (ITS) applications, this enabler could be used to, for example, send warning messages to warn other motorists of a road hazard in the vicinity of the sender. An application in another field may use it to send advertising messages by a shop owner to people entering the vicinity of the shop.
Here is a short tutorial video: