The Key Technologies For Traffic Information Services Based On REST Architecture

As an important component of the Intelligent Transportation Systems(ITS), the Traffic Information Service System(TISS) plays an important role in solving traffic problems. With the valid information provided by the TISS, participants and policy makers of relevant transportation systems can make their behaviors and decisions more effective, which will enhance economic and social benefits of the transportation systems. Along with fast development of computing, communication, sensing and control technologies, a growing number of Internet of things(IOT) technologies are applied to the TISS, which becomes the future direction of the TISS. In order to solve the scalability and openness problems existing in traditional traffic information service systems, this paper deeply studied the REST-style technologies of the TISS, and developed an intelligent gateway and traffic information data resource sharing and interoperability service platform(RESTful Traffic Information Service,RTIS). It includes the following:1. This paper proposed an intelligent gateway design scheme used the IOT technologies.In this scheme, the detailed design of the intelligent gateway is illustrated in three aspects,including hierarchical model design, physical structure design and logical structure design.For communication of the intelligent gateway, the RESTful API interface is designed to match the request-response pattern and the automatic reporting pattern.2. By analyzing requirements for sharing and interoperability of traffic data, an abstract model of traffic information data resources is proposed to implement unified abstraction for multi-source heterogeneous traffic data resources. Moreover, this paper also proposed a scheme to expose the RESTful API to communicate with application layer. For resource-constrained scenarios, a data compression approach is used to reduce bandwidth. For authorization, OAuth2.0 is used to protect exposed resources.3. According to the schemes proposed in the paper, a prototype of vehicle queue length detecting system based on sensor networks is designed and implemented. The RESTful API of the intelligent gateway, the performance of traffic information data resource accessing andthe data resource sharing capabilities are tested and validated in the prototype system.The test results showed that the sensing devices are easy to attach to the intelligent gateway and the intelligent gateway can be easily accessed through the RESTful API. The other testing results showed that the traffic information could be stored and shared by using the traffic information data service platform. And the traffic information data service platform met the requirement for sharing the traffic information data resources.