Research On MPTCP Transmission Optimization Algorithm For Short Flows

With the development and popularization of network technology,various electronic devices are also equipped with multiple network interfaces to facilitate Internet access.However,the mainstream network protocol used on electronic devices at this stage is still TCP.The protocol can only use one port for data transmission.The port is in an idle state.In order to improve the utilization of the network port,the researchers proposed the MPTCP(Multi-Path TCP)protocol.However,in the process of network transmission,MPTCP has obvious advantages for long-flow transmission.Due to the small amount of data,the completion time may increase.Therefore,how to shorten the completion time of short-flow is a research hotspot of MPTCP under the premise of ensuring the overall performance of the network.In this paper,based on the comprehensive analysis of the existing MPTCP scheduling algorithm,the MPTCP Transmission Optimization Algorithm for Short Flow(MPTCP-TOASF)is proposed.Under the premise of ensuring the effective throughput of the network,the completion time of the short flow is effectively reduced.The main work of the thesis is asfollows:(1)For the problem of long-short flow concurrent transmission and short-flow completion time increase,this paper proposes a short-flow MPTCP transmission optimization algorithm MPTCP-TOASF.The algorithm groups the paths according to the quality and flows the data according to the size of the data.It is divided into long and short flows,and the optimal path group is used to transmit the round-trip delay-sensitive short flow,and the long flow is transmitted in all path groups.When the optimal path group concurrently transmits long and short flows,the algorithm draws on the Veno congestion control idea,uses the delay-sensitive judgment mechanism,predicts the degree of path congestion,and controls the number of packets sent by the long-end of the sender,thus preventing packet loss in the short flow.The problem of long-flow encroachment on short-flow resources has effectively shortened the completion time of short-flow.(2)Using the NS-3 network simulation platform,the simulation experiment of the algorithm and TCP,MPTCP is carried out.In the experiment,the short-flow completion time,long-flow throughput and network effective throughput are used to evaluate the algorithm.Firstly,the algorithm is tested inthe case where only short-flow exists and the long-short flow coexists,and the long-short flow coexists.The performance of the algorithm was evaluated based on three factors: the number of short flows,the size of the short flow,and the number of subflows,and the reasonable value of the threshold was tested.Further,in order to get closer to the real environment,the algorithm was compared under the background flow.Finally,the experiment proves that MPTCP-TOASF improves the transmission performance of short-flow under the premise of ensuring the overall performance of the network.