| Summary: | 碩士 === 國立臺灣科技大學 === 電機工程系 === 102 === Following the improvement of technology, many kind of problems have been solved. The networking technology keeps updating for newer generation and changing the solution for connectivity. For example, the Software Defined Networking (SDN) is challenging traditional networking infrastructure. However, the vehicle systems are still under proprietary closed environment. Because of the safety, privacy, non-real-time update mechanism, and bad performance of network transport concerns, vehicle manufacturers still follow traditional principle of design and try to own the information ecosystem. As the latest generation mobile communication providing faster and stable backbone, this study seeks to implement the infrastructure of Software Defined Network (SDN) into telematics application. By using SDN and mobile communication technologies vehicle information systems can have a standard protocol and stable infrastructure.
This study was designed to research a diversity of applications that could provide a standard interfaces and functions for vehicle information systems. The aim is to integrate SDN into vehicle information systems in order to improve the performance. In this study, the Software Defined Network (SDN) is build based on OpenFlow Switch v1.3 and NOX Controller v1.3. The vehicle information framework is build in away that after parsing the CAN data of vehicle, then data is packaged into OpenFlow control message. When sending or replying information, either the controller or switch prepare the message for sending or receiving as OpenFlow messaging format. In addition to packaging the telematics messages into OpenFlow messages, this framework can be used in vehicle to vehicle communication as well.
The most ambitious part of this study is to provide an open interface and a standard protocol for the application of telematics. When comparing the application interface of OpenFlow with non-OpenFlow mechanism, this study found the performance of OpenFlow based mechanism is different. In the tests simulating only a few vehicles, the latency was shorter in non-OpenFlow based framework when sending or receiving messages. However, when simulating greater number of vehicles, due to multi-threaded performance of OpeFlow mechanism, the latency can be handled by the system thus providing more flexibility or better overall performance. Non-OpenFlow mechanism might not take into account a larger number of multithreading, thus the latency performance may not be stable. In the tests in this study the different of latency between OpenFlow and non-OpenFlow mechanism was found to be 6.4% for the advantage of non-OpenFlow mechanism. However, while accounting for multithreaded performance, when the number of vehicles increases, the OpenFlow mechanism can provide a better performance than non-OpenFlow mechanism.
In conclusion, while comparing the V2V SDN and the V2V DSRC the result of the simulation shows that the latency of V2V SDN is shorter than V2V DSRC, when the network of vehicles consists of more than 8 vehicles.
|
|---|
