RFC 4821 · PROPOSED STANDARD · 2007

Packetization Layer Path MTU Discovery

Overview

RFC 4821, “Packetization Layer Path MTU Discovery”, is a Proposed Standard document published in March 2007 by M. Mathis, J. Heffner. It has since been updated by RFC 8899. The canonical text is published by the RFC Editor.

Abstract

This document describes a robust method for Path MTU Discovery (PMTUD) that relies on TCP or some other Packetization Layer to probe an Internet path with progressively larger packets. This method is described as an extension to RFC 1191 and RFC 1981, which specify ICMP-based Path MTU Discovery for IP versions 4 and 6, respectively. [STANDARDS-TRACK]

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

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 4821 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Updated by
RFC 8899
Other RFCs from 2007

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