Design, analysis, and implementation of a large-scale real-time location-based information sharing system

Abstract

Today's Internet is incapable of handling information like a stop sign. Such information stays in a geographic region, consistently beams to the people who move into from certain direction. This paper presents a system aimed at bridging the Internet with the physical world. The hardware platform of the system consists of a central server and a set of position-aware mobile clients that communicate with the server through means of wireless networks. Each client has a capable zone, a circular region centered on its current position with a user-defined radius. Each piece of information managed by the server is a geopage, an HTML page associated with a geographic region. As clients move, they load with the geopages implanted in their surroundings. This paper identifies the technical challenges of managing a large number of geopages that spans over a large terrain with a large number of mobile clients, and proposes a cost-effective solution that minimizes mobile communication and server processing costs. We evaluate the scalability of the proposed technique with a detailed mathematical model. The accuracy of the model is verified using simulation. We have also implemented a prototype and field tested the system in several cities.