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Reverse DNS Naming Convention for CIDR Address Blocks

Document type: Expired Internet-Draft (individual)
Document stream: No stream defined
Last updated: 2013-08-29 (latest revision 2013-02-25)
Intended RFC status: Unknown
Other versions: (expired, archived): plain text, pdf, html

Stream State:No stream defined
Document shepherd: No shepherd assigned

IESG State: Expired
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found here:


This draft proposes a naming convention for encoding CIDR address blocks into the reverse DNS namespace. The reverse DNS naming method is commonly used to specify a complete IP address. This document describes how to encode an IPv4 or IPv6 CIDR address block such as By defining a common naming convention, one can associate information with a prefix. The convention builds on past work in RFC 1101 that associates network names with prefixes. However, this previous work pre-dated the introduction of CIDR and has several critical ambiguities. This convention corrects the ambiguities and enables new applications ranging from routing information to geolocation.


Joe Gersch <>
Dan Massey <>
Eric Osterweil <>
Cathie Olschanowsky <>

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid)