On the suitability of BBR congestion control for QUIC over GEO SATCOM networks

Abstract

Satellite broadband connectivity has received significant level of interest in recent years, partly due to the emergence of 5th and 6th generations of cellular networks and their novel use-cases. High-throughput GEO satellites are therefore expected to become an integral part of such networks both for access and backhauling. Almost simultaneously, major breakthroughs have occurred within the Internet transport layer - i.e., with the increasing deployment of user-space QUIC protocol and BBR congestion control. The impact of these innovations and their overall performance on the Internet paths traversing over satellite links is yet to be investigated. Although traditionally TCP-splitting methods with Performance-Enhancing-Proxies (PEPs) were used to boost the transport performance over the satellite links, such approaches become hard for QUIC due to its encrypted nature. This leads to QUIC's poor performance over satellite links, which is currently being investigated by the IETF's QUIC WG. In addition, the transport performance depends on the choice of congestion control and QUIC implementation. In this work we will explore these aspects and the suitability of BBR congestion control for QUIC over SATCOM networks through real-life experimentation in an emulated testbed environment.