RFC 8548 · EXPERIMENTAL · 2019

Cryptographic Protection of TCP Streams

Overview

RFC 8548, “Cryptographic Protection of TCP Streams”, is an Experimental document published in May 2019 by A. Bittau, D. Giffin, M. Handley, D. Mazieres, Q. Slack, E. Smith. The canonical text is published by the RFC Editor.

Abstract

This document specifies "tcpcrypt", a TCP encryption protocol designed for use in conjunction with the TCP Encryption Negotiation Option (TCP-ENO). Tcpcrypt coexists with middleboxes by tolerating resegmentation, NATs, and other manipulations of the TCP header. The protocol is self-contained and specifically tailored to TCP implementations, which often reside in kernels or other environments in which large external software dependencies can be undesirable. Because the size of TCP options is limited, the protocol requires one additional one-way message latency to perform key exchange before application data can be transmitted. However, the extra latency can be avoided between two hosts that have recently established a previous tcpcrypt connection.

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 8548 is hosted at rfc-editor.org. Available in TXT,HTML.

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