vehicles’ GPS-enabled On-board Unit
accident notification
intuitive
intrinsically
offline based applications
back-end server
a centralized database to store  
To respond to these trends
例子:使用轨迹无意义的跨区
sufficiently
The results show that highest density of WiFi hotspots corresponds to residential areas. The distribution of WiFi hotspots is naturally related to the population density in the city, since WiFi hotspots are deployed in close to every household, offices, shops or public places.
suburb
natural boarders
location awareness
A city populated by 1 million people will produce 180 PB data per day by 2019 [9], contributed by public safety, health, utility, and transports, etc.  
For applications that require predictable and low latency such as health emergency or public safety
Buffer Management for Synchronous and Low-Latency Playback of Multi-Stream User-Generated Content
predominantly