QUIC Throughput and Fairness over Dual Connectivity

TL;DR

This study investigates how Dual Connectivity affects QUIC protocol performance, revealing impacts on throughput and fairness under various network conditions and configurations, providing insights for network optimization.

Contribution

First comprehensive analysis of QUIC performance over Dual Connectivity, examining effects of parameters, network variability, and implementation choices on throughput and fairness.

Findings

QUIC performance over DC is similar to TCP with proper parameters.

Increased UDP buffers improve QUIC throughput over DC.

Fairness is achieved under symmetric links when DC isn't used for duplication.

Abstract

Dual Connectivity (DC) is an important lower-layer feature accelerating the transition from 4G to 5G that also is expected to play an important role in standalone 5G radio networks. However, even though the packet reordering introduced by DC can significantly impact the performance of upper-layer protocols, no prior work has studied the impact of DC on QUIC. In this paper, we present the first such performance study. Using a series of throughput and fairness experiments, we show how QUIC is affected by different DC parameters, network conditions, and whether the DC implementation aims to improve throughput or reliability. Results for two QUIC implementations (aioquic, ngtcp2) and two congestion control algorithms (NewReno, CUBIC) are presented under both static and highly time-varying network conditions. Our findings provide network operators with insights and understanding into the impacts of splitting QUIC traffic in a DC environment. With reasonably selected DC parameters and increased UDP receive buffers, QUIC over DC performs similarly to TCP over DC and achieves optimal fairness under symmetric link conditions when DC is not used for packet duplication. The insights can help network operators provide modern users with better end-to-end service when deploying DC.