RFC 8553 · BEST CURRENT PRACTICE · 2019

DNS Attrleaf Changes: Fixing Specifications That Use Underscored Node Names

Overview

RFC 8553, “DNS Attrleaf Changes: Fixing Specifications That Use Underscored Node Names”, is a Best Current Practice document published in March 2019 by D. Crocker. It updates RFC 2782, RFC 3263, RFC 3529, RFC 3620, RFC 3832, RFC 3887, RFC 3958, RFC 4120, RFC 4227, RFC 4386, RFC 4387, RFC 4976, RFC 5026, RFC 5328, RFC 5389, RFC 5415, RFC 5518, RFC 5555, RFC 5617, RFC 5679, RFC 5766, RFC 5780, RFC 5804, RFC 5864, RFC 5928, RFC 6120, RFC 6186, RFC 6376, RFC 6733, RFC 6763, RFC 7208, RFC 7489, RFC 8145. The canonical text is published by the RFC Editor.

Abstract

Using an underscore for a prefix creates a space for constrained interoperation of resource records. Original uses of an underscore character as a domain node name prefix were specified without the benefit of an IANA registry. This produced an entirely uncoordinated set of name-creation activities, all drawing from the same namespace. A registry for these names has now been defined by RFC 8552. However, the existing specifications that use underscored naming need to be modified in order to be in line with the new registry. This document specifies those changes. The changes preserve existing software and operational practice, while adapting the specifications for those practices to the newer underscore registry model.

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

The canonical text of RFC 8553 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
Other RFCs from 2019

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