Research On Key Technologies Of VDES Satellite Network Routing Based On SDN

VHF Data Exchange System(VDES)is a new generation of digital communication system in the field of maritime mobile services based on the Automatic Identification System(AIS).VDES is designed to provide higher and stronger data exchange capabilities in the global range of the maritime VHF mobile bands,and enable ships to send or retrieve information from ports,chart information centers,and so on.VDES uses satellite communications as a means of telematics.Network routing technology is the key component of satellite network transmission.With the increase of VDES service types,different services need different QoS,the merits of the routing algorithm directly determine the performance of VDES.First of all,the existing satellite network control architecture is fixed,software upgrades is difficult and it's hard to update the network configuration and so on.The thesis introduced the software-defined networking to design a software-defined satellite networking architecture.By decoupling the control function and data forwarding function,Satellite node can only process the data packet based on flow table.The network controller is realized by the professional controller in the form of software.By SDN,we can reduce the network complexity,achieve the automation of services deployment,and improve the utilization of network resource.Then,most of the existed satellite routing algorithms are optimized a single QoS target.So those routing algorithms can not adapt to meet the needs of multi-QoS targets.Based on the satellite environment,the thesis combines the available bandwidth,packet loss rate,link end to end delay as the multi-QoS target,proposes a multi-QoS target routing algorithm based on ant colony algorithm.In this thesis,to solve the inherent defects of ant colony algorithm such as convergence slowly and easy to converge to the local optimal solution,the corresponding improvement strategy is puting forward based on the software-defined networking technology.Finally,the thesis designs a terrestrial hardware-in-the-loop simulation test platform based on cloud platform resource management technology,host and network virtualization technology and software-defined networking technology.Then the thesis evaluates the performance of multi-QoS target routing algorithm in the satellite network.The simulation results show that the multi-QoS target routing algorithm proposed in this thesis can meet the needs of different users' multi-service conditions.