rLEDBAT: Receiver-Driven Low Extra Delay Background Transport for TCP
RFC 9840, “rLEDBAT: Receiver-Driven Low Extra Delay Background Transport for TCP”, is an Experimental document published in September 2025 by M. Bagnulo, A. García-Martínez, G. Montenegro, P. Balasubramanian. The canonical text is published by the RFC Editor.
Abstract
This document specifies receiver-driven Low Extra Delay Background Transport (rLEDBAT) -- a set of mechanisms that enable the execution of a less-than-best-effort congestion control algorithm for TCP at the receiver end. This document is a product of the Internet Congestion Control Research Group (ICCRG) of the Internet Research Task Force (IRTF).
What “Experimental” means
Describes a specification that is part of a research or development effort, published so the community can gain experience with it.
The canonical text of RFC 9840 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.
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