| The rapid development of communication technology has led to the increasing popularity of terminal equipment with multiple network interfaces.Multi-path parallel transmission technology,refers to the aggregation of bandwidth,to achieve rapid transmission of data and to improve the utilization of idle resources on the network.Traditional multi-path technology more consider the same type of network environment,but the lack of consideration of the network heterogeneity.However,the heterogeneous network due to the asymmetry of the performance of each link has different packet transmission delay,and may lead to receiver data out of order phenomenon occurs,and even will cause the receiver cache block and seriously affect the parallel transmission system throughput performance.Therefore,in order to improve the performance of multipath parallel transmission system in heterogeneous networks and improve the overall throughput of the network,this thesis makes the following research.Firstly,the problem of packet unordered caused by multipath parallel transmission in heterogeneous network environment is studied deeply,and the related factors of packet unordered are analyzed.A model based on end-to-end delay cumulative probability distribution is proposed.Based on the existing research results,the model increases the influence of the sender queuing delay and improves the accuracy of the model.And then use this model to deduce the constraint condition of packet ordered transmission and the calculation formula of packet outordered probability.The simulation results show that the outordered probability curve of the data packet is consistent with the simulation curve,and the validity of the model is verified.Secondly,in order to reduce the occurrence of out-of-order in receiver at the constraint condition of packet order transmission,this thesis put forward a trassmission delay prediction based Kalman Filter algorithm.The algorithm first gives the effective evaluation scheme of the path transmission delay.When predict the time of the data chunk arrives at the receiver,the queuing delay of the data chunk at the sender is introduced,the accuracy of the prediction is improved.Accurate scheduling,effectively reducing the receiver data out of order to improve the overall throughput of the network performance.The TDP-KF algorithm is proved to be correct and effective by the simulation results. |
