Special Use Domain Name 'ipv4only.arpa'

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Document Type Expired Internet-Draft (individual)
Authors Stuart Cheshire  , David Schinazi 
Last updated 2019-05-07 (latest revision 2018-11-03)
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The specification for how a client discovers its local network's NAT64 prefix [RFC7050] defines the special name 'ipv4only.arpa' for this purpose, but in its Domain Name Reservation Considerations section that specification indicates that the name actually has no particularly special properties would require special handling, and does not request IANA to record the name in the Special-Use Domain Names registry. Consequently, despite the well articulated special purpose of the name, 'ipv4only.arpa' was not recorded in the Special-Use Domain Names registry as a name with special properties. As a result of this omission, in cases where software needs to give this name special treatment in order for it to work correctly, there was no clear mandate authorizing software authors to implement that special treatment. Software implementers were left with the choice between not implementing the special behavior necessary for the name queries to work correctly, or implementing the special behavior and being accused of being noncompliant with some RFC. This document describes the special treatment required, formally declares the special properties of the name, and adds similar declarations for the corresponding reverse mapping names.


Stuart Cheshire (cheshire@apple.com)
David Schinazi (dschinazi.ietf@gmail.com)

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