RFC 6891 · INTERNET STANDARD · 2013

Extension Mechanisms for DNS (EDNS )

Overview

RFC 6891, “Extension Mechanisms for DNS (EDNS )”, is an Internet Standard document published in April 2013 by J. Damas, M. Graff, P. Vixie. It obsoletes RFC 2671, RFC 2673. The canonical text is published by the RFC Editor.

Abstract

The Domain Name System's wire protocol includes a number of fixed fields whose range has been or soon will be exhausted and does not allow requestors to advertise their capabilities to responders. This document describes backward-compatible mechanisms for allowing the protocol to grow.

This document updates the Extension Mechanisms for DNS (EDNS(0)) specification (and obsoletes RFC 2671) based on feedback from deployment experience in several implementations. It also obsoletes RFC 2673 ("Binary Labels in the Domain Name System") and adds considerations on the use of extended labels in the DNS.

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

What “Internet Standard” means

A mature, widely-implemented specification that has completed the full IETF standards process — the highest maturity level on the standards track.

Read this RFC

The canonical text of RFC 6891 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC obsoletes
RFC 2671 RFC 2673
Other RFCs from 2013

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