RFC 8312

CUBIC for Fast Long-Distance Networks, February 2018

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Obsoleted by:
RFC 9438
I. Rhee
L. Xu
S. Ha
A. Zimmermann
L. Eggert
R. Scheffenegger
tcpm (wit)

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DOI:  https://doi.org/10.17487/RFC8312

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CUBIC is an extension to the current TCP standards. It differs from the current TCP standards only in the congestion control algorithm on the sender side. In particular, it uses a cubic function instead of a linear window increase function of the current TCP standards to improve scalability and stability under fast and long-distance networks. CUBIC and its predecessor algorithm have been adopted as defaults by Linux and have been used for many years. This document provides a specification of CUBIC to enable third-party implementations and to solicit community feedback through experimentation on the performance of CUBIC.

For the definition of Status, see RFC 2026.

For the definition of Stream, see RFC 8729.

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