RFC 9743 · BEST CURRENT PRACTICE · 2025

Specifying New Congestion Control Algorithms

Overview

RFC 9743, “Specifying New Congestion Control Algorithms”, is a Best Current Practice document published in March 2025 by M. Duke, G. Fairhurst. It obsoletes RFC 5033. The canonical text is published by the RFC Editor.

Abstract

RFC 5033 discusses the principles and guidelines for standardizing new congestion control algorithms. This document obsoletes RFC 5033 to reflect changes in the congestion control landscape by providing a framework for the development and assessment of congestion control mechanisms, promoting stability across diverse network paths. This document seeks to ensure that proposed congestion control algorithms operate efficiently and without harm when used in the global Internet. It emphasizes the need for comprehensive testing and validation to prevent adverse interactions with existing flows.

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

What “Best Current Practice” means

Documents the IETF community's recommended operational or procedural practice rather than a protocol specification.

Read this RFC

The canonical text of RFC 9743 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

Relationships to other RFCs
This RFC obsoletes
RFC 5033
Other RFCs from 2025

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