Research On Multipath Transmission In Network And Its Application In Real-time Streaming Media

With the continuous development of network technology,network users put forward higher requirements for quality of service(QoS)of network communication services,especially real-time transmission services.Traditional networks usually use shortest path routing and single path transmission,which will affect the quality of network transmission and even cause network interruption when the path fails.It brings challenges to improve the quality of network service.Therefore,exploring connection-oriented multipath transmission has become one of the research hotspots.This thesis proposes two multipath transmission methods in network layer,which can improve network performance and improve network quality of service with a lower cost.Vector Network(VN)is a new type of connection-oriented communication network,which has the advantages of low cost,high security and multipath support.Using the multipath capability of VN can improve network reliability,QoS and other performance,but how to perceive the state of the path in order to switch the fault path in time is the first problem to be solved.In this thesis,the most challenging communication service,voice,is taken as an example to illustrate the effectiveness of methods.The main work and achievements are as follows:(1)A transmission method named End-to-end Multipath Handover in VN,MPH-VN for short,is designed.In this method,path handover is introduced.Based on this,a path anomaly detection method based on time interval measurement and a path handover method based on anomaly information feedback are designed,which can sense the state of the path in time and switch the anomaly path.At the same time,a certain amount of packet loss and retransmit is carried out,which can effectively reduce the packet loss.The simulation results show that the method can effectively improve the end-to-end transmission quality.(2)A transmission method named End-to-end Multipath Rotation in VN,MPR-VN for short,is designed,which utilizes the loss counting mechanism to monitor the path state.The simulation results show that this method can avoid a large number of packet dropouts caused by abnormal paths and reduce end-to-end delay when applied to VN.(3)The VN OMNET simulation platform is designed and implemented,which can support protocols of VN.Using the logic structure of VN,network objects of VN are simulated and designed.The definition of the vector data packet format for the multipath transmission process in VN is given,and the network fault model is designed to simulate the abnormal situation in the real network environment.In summary,two multipath transmission methods,MPH-VN and MPR-VN,are proposed,and a OMNET simulation platform for VN is established.The simulation results show that MPH-VN and MPR-VN can effectively reduce the packet loss rate and network delay in the process of network transmission,and improve the transmission quality of voice real-time streaming media compared with the traditional transmission mode of IP network.