Reducing latency in Internet Access Links

Excessive and unpredictable end-to-end latency is a major problem for today’s Internet performance, affecting a range of applications from real-time multimedia to web traffic. This is mainly attributed to the interaction between the TCP congestion control and the unmanaged large buffers deployed across the Internet. In this talk I will discuss transport and link layer solutions to solve the Internet’s latency problem on the access links. These solutions operate on the sender side, within the network or use signaling between the sender and the network based on Explicit Congestion Notification (ECN). In addition, I will present Alternative Backoff with ECN (ABE), a change in sender’s reaction to ECN signal that reduces latency without harming link utilization. Real-life experiments and simulations show that this goal is achieved while maintaining backward compatibility and being gradually deployable on the Internet. ABE has been standardized by the IETF as an “experimental” RFC (RFC 8511) and been incorporated into mainline FreeBSD kernel.