RFC 8558 · INFORMATIONAL · 2019

Transport Protocol Path Signals

Overview

RFC 8558, “Transport Protocol Path Signals”, is an Informational document published in April 2019 by T. Hardie. The canonical text is published by the RFC Editor.

Abstract

This document discusses the nature of signals seen by on-path elements examining transport protocols, contrasting implicit and explicit signals. For example, TCP's state machine uses a series of well-known messages that are exchanged in the clear. Because these are visible to network elements on the path between the two nodes setting up the transport connection, they are often used as signals by those network elements. In transports that do not exchange these messages in the clear, on-path network elements lack those signals. Often, the removal of those signals is intended by those moving the messages to confidential channels. Where the endpoints desire that network elements along the path receive these signals, this document recommends explicit signals be used.

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

What “Informational” means

Published for the general information of the community. It does not define an IETF standard and carries no standards-track status.

Read this RFC

The canonical text of RFC 8558 is hosted at rfc-editor.org. Available in TXT,HTML.

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