QUIC传输机制与应用综述

Review on QUIC Transmission Mechanism and Application

QUIC作为与TCP并行的新兴传输协议,在传统传输协议的基础上改进了诸多特性,如0-RTT数据传输、多流并发、热插拔拥塞控制等。由于QUIC具有安全、公平、兼容且高性能等特性,被业界认为将在未来网络的New IP构想中替代TCP成为新一代传输协议。QUIC协议经过近6年的研究已经完成标准化,其间研究人员提出多种针对不同应用场景的开源实现和测试开发工具,也针对QUIC在现实网络中的应用进行了大量探索。从QUIC的特征机制以及开源实现出发,阐述QUIC协议从出现到标准化这期间的开发历程,归纳QUIC与TCP在传输特性方面的差异性,并分析QUIC在广泛应用部署过程中存在的性能短板。针对这些短板,从协议设计、协议部署、I/O优化处理这3个方面列举当前已有的典型优化实现方法。进一步探究QUIC的传输特性,从不同版本开源QUIC之间的性能对比、互操作和功能验证等3个方面进行总结和归纳,并对QUIC协议在当前网络生态中的相关应用进行举例分析。在此基础上,针对QUIC应用在New IP构想中的未来优化方向加以展望。

Quick UDP Internet Connection(QUIC),as an emerging parallel transmission protocol within TCP,has improved many features based on traditional transmission protocols,such as 0-RTT data transmission,multi stream concurrency,and hot plug congestion control.Due to its characteristics of security,fairness,compatibility,and high performance,QUIC is considered by industry as a replacement of TCP for next-generation transmission protocols in the future Network 2030 and the Future of IP(New IP)concept of networks.After nearly 6 years of research,the QUIC protocol has been standardized.During this period,researchers have proposed various open-source implementation and testing development tools for different application scenarios and have conducted extensive exploration of the application of QUIC in real networks.Started from the characteristic mechanism and open-source implementation of QUIC,the development process of the QUIC protocol is elaborated from its emergence to standardization,the differences in transmission characteristics between QUIC and TCP are summarized,and the performance shortcomings of QUIC regarding its widespread application and deployment are analyzed.To address these shortcomings,typical optimization implementation methods that are currently available are considered from three aspects:protocol design,protocol deployment,and I/O optimization processing.To further explore the transmission characteristics of QUIC,a performance comparison between different versions of open source QUIC,interoperability,and functional verification is performed,and the relevant applications of the QUIC protocol in the current network ecology are analyzed.On this basis,prospects for future optimization of the QUIC application within the New IP concept are proposed.