Internet Connection Splitting - What's Old is New Again

Explore the continued relevance of performance-enhancing proxies (PEPs) in modern internet infrastructure through this 14-minute conference presentation from USENIX ATC '25. Examine how connection-splitting technology from the 1990s, originally designed to improve TCP performance over lossy and high-latency networks, performs against contemporary protocols and algorithms. Analyze comprehensive emulation measurements comparing the effectiveness of PEPs with recent versions of the BBR congestion-control algorithm, discovering that newer BBR implementations benefit significantly from connection-splitting, sometimes even more than traditional loss-based congestion-control methods. Investigate the dramatic variations in QUIC protocol implementations of identical congestion-control algorithms and understand how these differences complicate direct performance comparisons with Linux TCP. Learn why, despite the emergence of QUIC transport protocol and advanced congestion control mechanisms, performance-enhancing proxies remain a valuable tool for optimizing internet performance in challenging network conditions.