QUIC(k) Enough in the Long Run? Sustained Throughput Performance of QUIC Implementations

QUIC aims to become a general-purpose transport protocol, and numerous implementations of the QUIC protocol already exist. Earlier evaluations often examined QUIC in conjunction with HTTP/3.0 or focused on latency metrics. The measurement studies in this paper focus on actual QUIC implementations with respect to their ability to achieve high sustained throughput in network scenarios with data rates of 10 Gbit/s. We compare six popular QUIC implementations developed in different programming languages with TCP. Our findings show significant performance improvements in several QUIC implementations compared to prior evaluations. However, it is not a homogeneous picture, as current QUIC implementations often behave quite differently. We observed that in environments with low RTTs or an increased number of packet losses, most of the surveyed QUIC implementations struggle unexpectedly and cannot compete with TCP regarding sustained throughput performance.