The Design Of AIS Communication Server Based On Node.js

In recent years, with the rapid development of the domestic shipping industry, the quantity of ships in navigable waters has grown rapidly. However, at the same time, the increasing quantity of ships and traffic density has a serious impact on the ecological environment and traffic safety of the navigable waters. In order to guarantee the safety of navigation, strengthen the management of the ship, The AIS base station network system covered river and coastal areas waters has been established in China. The signal has covered the important navigable waters and ports of coastal and inland countrywide.AIS server is designed to receive AIS data with the feature of large quantity and real time. Nevertheless, in order to avoid occurrences of data congestion, missing, etc. during communication, it requires the communication links with the AIS base stations stable, reliable, and able to meet the needs of real-time communication. Currently, the most of AIS communication servers are developped with VC++ technology. They receive a variety of information via the network port or the serial interface of the PC linking with AIS base station, which is sent by sailing vessels through the network.Node.js, is a platform which allows JavaScript to run on the server side. It has abandoned the design ideas of the traditional platform which rely on multi-threading to achieve high concurrency. However, it adopted single-threaded, asynchronous I/O, event-driven programming model. It has turned out to be suitable for server design with the characteristic of high concurrency, real-time response and ultra-large-scale data.Therefore, this paper proposes to develop AIS communication server based on Node.js technology to ensure the stability, reliability, real-time data transmission and large-scale data transmission of communication link between the AIS base station and communications server.The main work in this thesis:(1) This paper analyzes the role of AIS communication server, introduces Node.js technology and its features, proposes the development of AIS communications server based on Node.js technology.(2) According to the actual needs, the AIS communication server is designed with Node.js technology. According to the functions of each part, this paper designs the server modules:the TCP server based on Node.js technology; AIS message parsing module which is based on the Node.js and C++ extension methods; data storage module based on MongoDB database; In addition, in order to conduct test for server, simulation station based on Node.js technology is designed.(3) The method of building development platform is introduced in detail. Based on Node.js technology and VS2010 development platform, development of the AIS communication server has been finished. And the performance of the server are tested and analyzed.