Design And Implementation Of Network Monitoring Device For Ship Navigation System

With the continuous development of network technology, network technology has beenapplied to all areas of society, also establishing a comprehensive information networkplatform is the modern trend of the ship systems development in the future. The shipnavigation system gradually realize the network，and communication technology has becomemore and more advanced. In the1980s serial communication was the main means ofcommunication, with the increasing demand of performance, CAN network and Ethernetnetwork have been used in ship navigation system, and reflective memory technology as anew technology will be applied to navigation system. As the continuous expansion of the shipnavigation system network size and more complicated, real-time understanding of networkoperating status, testing and evaluation of network performance are becoming more and moreurgent. Network monitoring system can solve these problems very well, so in this paperaccording to the needs of ship navigation system network development the overall designscheme for the monitoring device of ship navigation system network was put forward.Firstly, according to the analysis about the demand of the network monitoring functions,the functions and the performance requirements of network monitoring device are designed.The overall design of device hardware and software platform also is completed, and on thebasis of VxWoks operating system as software development platform, the graphicaldevelopment tool--Tilcon is used to develop graphical interface. The design of monitoringsystem structure of CAN network, Ethernet and reflective memoty network is completed.Then, according to the characteristics of ship navigation system network, the capture andstorage system is designed and implemented. Since the transmission of Ethernet data isthrough protocol stack encapsulation and decomposition, so the design of the capture systemis mainly for the Ethernet data acquisition design.The capture scheme is designed on the basisof study of VxWorks operating system and capture technology. The capture ability isimproved by improvement of capture technology. The file storage system and database systemare introduced, and storage system is designed and implemented. Storage system which isachieved by file system—dosFs and embedded database—Berkeley DB is composed of filestorage and database storage.Secondly, the key modules of network monitoring system which include the Ethernetprotocol analysis module, CAN network troubleshooting and statistics module, reflectivememory network node monitoring module and reading and writing module are designed andimplemented. It makes a careful analysis of each module to realize the function, and describes design and realization of the key module in detail.Finally, the network monitoring device functions are tesed by the simulationenvironment which is composed of CAN network, Ethernet and reflective memory network.Performance testing mainly includes the capture performance of the capture system and thereading and writing performance testing of the storage system.The results show that thefunctions of monitoring devices have achieved and the results meet the requirements.