Research And Implementation Of Traffic Information Service System Based On SOA

Modern society based on information technology make it necessary of utilizing the computer technology and Internet to improve the management efficiency of transportation system. The traffic information service system(TISS) has become a promising way of solving this problem by collecting the traffic information and sending real-time instruction to the transporter. Due to the internal features of TISS such as system heterogeneity, syntax heterogeneity and so forth, Service-Oriented Architecture(SOA) become the first choice of building TISS.This paper illustrates the concept of intelligent transportation system(ITS), TISS in the first part, especially the history, definition, current research status and shortcomings at home and abroad. Then according to the characteristics of TISS, we interpret the basic ideas of choosing SOA as the framework of building TISS.After expounding the core concept and architecture of SOA, we discuss some of the development technology of SOA in Java. As service invocation is the basis of SOA, we give a comparison of the commonly-used service communication framework, including the famous Web Services, which is used in our TISS design. In order to divide the application into modules, we use OSGi, a Java module developing technology as the underlying framework of the system.Based on Java platform, a TISS software infrastructure aiming at service governance is proposed, using OSGi as the component container, Spring as the bean manager and Web Services as the service component. It could utilize the existing software and middleware resources and exhibits clear structure, high development efficiency and great convenience of building distributed system. In this paper, a detailed interpretation of both the development and runtime model of TISS is given, including the process of service publishing and consuming, which reflects the design philosophy of SOA. Beyond all this, this paper describes the theory and implementation of Service Registration Center, as well as some practice of improving the system capacity and achieving load balance. These are very important to building a large scale and high available distributed traffic information service system.Based on the development architecture discussed above, we give the implementation of a Traffic Information Dissemination System, which could communicate between two heterogeneous systems by using Web Service and display real-time traffic condition on Variable Message Sign(VMS). At last, we conclude with summarizing the shortcomings and improvement directions of this TISS framework.