On the Application of LBS and the System Architecture of LBS-centric ITS

As the world becomes more mobile,getting the right location to the right people at the right time and place has ever been more important.In recent years,a new information service named location-based services(LBS) is coming forth as the result of the science and technology integration of GIS,mobile position,Internet,wireless network communication,and portable facilities.LBS has many applications in ITS'fields of vehicles navigation,tracing,monitoring,dispatch and security,occurrence response,geo-fence entered or exited notification,data collection,geographic-based tariffs,etc.From the point of view of system integration,LBS-centric ITS shows an advanced and cost-efficient alternative solution,which has a network-distributed,interoperable architecture,and is built with standard Internet and wireless communication protocols.Its multi-tiers architecture is composed of client layer,middleware layer,application service layer and data access layer.The top client layer is an individual information terminal bundled with GPS receiver,wireless communication module and data processing unit.The middleware layer is a suite of APIs designed to interface to any third party system,and it should support multiform position techniques. The application service layer encapsulates spatial server and other subsystem of ITS,providing services of map image,geocoding,proximity,route planning,certificate authority and accounting.The bottom data access layer stores and manages spatial information,traffic information and vehicles information.