School of Electronic Engineering and Computer Science

The State of the Art in (Linux) Congestion Control

27 February 2014

Time: 3:00 - 4:00pm


This talk goes into the last 3 years of research and development gone into dramatically improving response times for multiple internet applications (web, gaming and videoconferencing) while in congestion. It describes the depth of the bufferbloat problem on edge networks, has some new insights into packet pairing, touches upon improvements to TCP, and new protocols like mosh, and QUIC, and dives into the new codel, pie, and *fq_codel AQM and Packet Scheduling algorithms being deployed on DSL, cable, and core networks, and closes with the large list of remaining problems left to solve.

About the Speaker:

Dave Täht is the co-founder of the Bufferbloat project. He is also architect and chief bottle washer of the CeroWrt reference router project, which is exploring solutions to the bufferbloat, Wi-Fi and IPv6 and security problems on entirely open source consumer hardware. He is the original implementor of the CoDel algorithm in Linux, as well as maintainer of the ns2 and ns3 models of codel, and fq_codel, with multiple enhancements and derivatives, under test. To enhance testing of bufferbloat related fixes, he is also working on standardizing a “Realtime Response under Load” (RRUL) test suite, and on effectively measuring interpacket delays and loss under load with other new tools and techniques, and active in the ietf AQM, IPPM and RMCAT working groups.

Prior to tackling bufferbloat, he worked on wireless mesh networking, spacecraft, VOIP, and embedded Linux. He has been working on Unix-derived systems for 34 years.

He is the CTO of Teklibre, LLC, and associated with the LINCS lab in Paris and the Internet Systems Consortium (ISC). His present research is sponsored by Google Fiber.