RFC 3360 · BEST CURRENT PRACTICE · 2002

Inappropriate TCP Resets Considered Harmful

Overview

RFC 3360, “Inappropriate TCP Resets Considered Harmful”, is a Best Current Practice document published in August 2002 by S. Floyd. The canonical text is published by the RFC Editor.

Abstract

This document is being written because there are a number of firewalls in the Internet that inappropriately reset a TCP connection upon receiving certain TCP SYN packets, in particular, packets with flags set in the Reserved field of the TCP header. In this document we argue that this practice is not conformant with TCP standards, and is an inappropriate overloading of the semantics of the TCP reset. We also consider the longer-term consequences of this and similar actions as obstacles to the evolution of the Internet infrastructure.

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

What “Best Current Practice” means

Documents the IETF community's recommended operational or procedural practice rather than a protocol specification.

Read this RFC

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