Skip to main content

BBR Congestion Control

Document Type Expired Internet-Draft (individual)
Expired & archived
Authors Neal Cardwell , Yuchung Cheng , Soheil Hassas Yeganeh , Ian Swett , Van Jacobson
Last updated 2022-09-08 (Latest revision 2022-03-07)
RFC stream (None)
Intended RFC status (None)
Stream Stream state (No stream defined)
Consensus boilerplate Unknown
RFC Editor Note (None)
IESG IESG state Expired
Telechat date (None)
Responsible AD (None)
Send notices to (None)

This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:


This document specifies the BBR congestion control algorithm. BBR ("Bottleneck Bandwidth and Round-trip propagation time") uses recent measurements of a transport connection's delivery rate, round-trip time, and packet loss rate to build an explicit model of the network path. BBR then uses this model to control both how fast it sends data and the maximum volume of data it allows in flight in the network at any time. Relative to loss-based congestion control algorithms such as Reno [RFC5681] or CUBIC [RFC8312], BBR offers substantially higher throughput for bottlenecks with shallow buffers or random losses, and substantially lower queueing delays for bottlenecks with deep buffers (avoiding "bufferbloat"). BBR can be implemented in any transport protocol that supports packet-delivery acknowledgment. Thus far, open source implementations are available for TCP [RFC793] and QUIC [RFC9000]. This document specifies version 2 of the BBR algorithm, also sometimes referred to as BBRv2 or bbr2.


Neal Cardwell
Yuchung Cheng
Soheil Hassas Yeganeh
Ian Swett
Van Jacobson

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)