Research And Application Of Lightweight Congestion Control Mechanism Based On QUIC

A localized operating system is a partition system based on the ARINC653 standard.The TCP used in the transport layer in the network protocol stack is relatively bloated,and there is a problem of low transmission efficiency due to head-of-line blocking.With the rapid development of the network,the system can not meet the current transmission performance,and a good congestion control mechanism can greatly improve its transmission performance.The emergence of the UDP-based QUIC protocol,on the premise of ensuring the security and reliability of data,can also satisfy multiple transmissions and is relatively lightweight.This paper proposes a QUIC-based lightweight congestion control mechanism that meets the performance requirements of a localized operating system,and applies it to the localized operating system to design a safe and reliable device with high transmission performance for the next step.The lightweight protocol stack has laid a good foundation.The main research work is as follows:(1)A congestion prediction method is proposed.Aiming at the problem of inaccurate judgment caused by traditional congestion control only relying on packet loss to determine whether the network is congested,the round-trip delay RTT is introduced.The experimental results show that when the bit error rate reaches 0.01%,the average throughput of the network after using the link congestion prediction method is increased by 34.4% compared with that without the link congestion prediction method.(2)An improved QCubic congestion control algorithm is proposed,whose core content is fast retransmission and fast recovery mechanism.Aiming at the problem that the congestion window adjustment period is long and the adjustment is not timely in the QUIC-based Cubic algorithm,based on the congestion window growth function of the QUIC-based Cubic algorithm,a network congestion degree awareness mechanism based on network delay and dynamic The adjustment mechanism,that is,according to the link-aware algorithm to perceive the current network compared with the last congestion result,and dynamically adjust the slow-start threshold and the size of the congestion window in time.Experiments show that the improved QCubic algorithm can further to improve the fairness and network utilization of the network.(3)The improved QUIC-based lightweight congestion control is applied to / for a localized operating system.Redesign the architecture of a localized operating system network protocol stack,added a QUIC user-mode transport layer,implemented the UDP-based QUIC protocol,and applied the congestion prediction method and improved congestion control mechanism proposed to this paper.This paper builds a simulation environment in NS3,conducts experiments from three aspects of throughput,fairness and friendliness,and makes a comparative analysis with the Cubic algorithm based on QUIC.The simulation results show that under the premise of ensuring fairness and friendliness,the average throughput of the link using the QCubic algorithm is 34.4% higher than that of the link using the QUIC-based Cubic algorithm.At the same time,the network protocol stack is deployed in Vx Works for application testing.The experimental results show that the throughput of the network protocol stack using the QCubic algorithm is increased by3.32%?6.46% compared to the network protocol stack using the QUIC-based Cubic algorithm.