RFC 7413 · EXPERIMENTAL · 2014

TCP Fast Open

Overview

RFC 7413, “TCP Fast Open”, is an Experimental document published in December 2014 by Y. Cheng, J. Chu, S. Radhakrishnan, A. Jain. The canonical text is published by the RFC Editor.

Abstract

This document describes an experimental TCP mechanism called TCP Fast Open (TFO). TFO allows data to be carried in the SYN and SYN-ACK packets and consumed by the receiving end during the initial connection handshake, and saves up to one full round-trip time (RTT) compared to the standard TCP, which requires a three-way handshake (3WHS) to complete before data can be exchanged. However, TFO deviates from the standard TCP semantics, since the data in the SYN could be replayed to an application in some rare circumstances. Applications should not use TFO unless they can tolerate this issue, as detailed in the Applicability section.

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

What “Experimental” means

Describes a specification that is part of a research or development effort, published so the community can gain experience with it.

Read this RFC

The canonical text of RFC 7413 is hosted at rfc-editor.org. Available in TXT,HTML.

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