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Top-level Domains for Private Internets

Document Type Replaced Internet-Draft (dnsop WG)
Expired & archived
Authors Roy Arends , Ed Lewis
Last updated 2020-09-29 (Latest revision 2020-06-08)
Replaced by draft-ietf-dnsop-private-use-tld
RFC stream Internet Engineering Task Force (IETF)
Intended RFC status (None)
Additional resources Mailing list discussion
Stream WG state Adopted by a WG
Document shepherd (None)
IESG IESG state Replaced by draft-ietf-dnsop-private-use-tld
Consensus boilerplate Unknown
Telechat date (None)
Responsible AD (None)
Send notices to (None)

This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:


There are no defined private-use namespaces in the Domain Name System (DNS). For a domain name to be considered private-use, it needs to be future-proof in that its top-level domain will never be delegated from the root zone. The lack of a private-use namespace has led to locally configured namespaces with a top-level domain that is not future proof. The DNS needs an equivalent of the facilities provided by BCP 5 (RFC 1918) for private internets, i.e. a range of short, semantic-free top-level domains that can be used in private internets without the risk of being globally delegated from the root zone. The ISO 3166 standard is used for the definition of eligible designations for country-code top-level Domains. This standard is maintained by the ISO 3166 Maintenance Agency. The ISO 3166 standard includes a set of user-assigned code elements that can be used by those who need to add further names to their local applications. Because of the rules set out by ISO in their standard, it is extremely unlikely that these user-assigned code elements would ever conflict with delegations in the root zone under current practices. This document explicitly reserves these code elements to be safely used as top-level domains for private DNS resolution.


Roy Arends
Ed Lewis

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