RFC 9406 · PROPOSED STANDARD · 2023

HyStart++: Modified Slow Start for TCP

Overview

RFC 9406, “HyStart++: Modified Slow Start for TCP”, is a Proposed Standard document published in May 2023 by P. Balasubramanian, Y. Huang, M. Olson. The canonical text is published by the RFC Editor.

Abstract

This document describes HyStart++, a simple modification to the slow start phase of congestion control algorithms. Slow start can overshoot the ideal send rate in many cases, causing high packet loss and poor performance. HyStart++ uses increase in round-trip delay as a heuristic to find an exit point before possible overshoot. It also adds a mitigation to prevent jitter from causing premature slow start exit.

Abstract as published in the RFC, via rfc-editor.org.

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 9406 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

Other RFCs from 2023

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