RFC 4282, "The Network Access Identifier", December 2005

Note: This RFC has been obsoleted by RFC 7542

Errata ID: 1623
Status: Rejected
Type: Technical
Publication Format(s) : TEXT
Reported By: Martin Thomson
Date Reported: 2008-12-01
Rejected by: Dan Romascanu
Date Rejected: 2009-02-05

Section 2.1 says:

   realm       =  1*( label "." ) label

It should say:

   realm       =  *( label "." ) label

Notes:

The ABNF for realm forces the inclusion of two labels, which is not consistent with RFC 1034, which allows just one:
<subdomain> ::= <label> | <subdomain> "." <label>
--VERIFIER NOTES--
Not allowing single-label realms was a deliberate decision (and the examples of invalid NAIs in Section 2.8 also include this case). One of the reasons was that RFC 1034 considers names without dots to be "relative" names of local significance. Such names may be valid DNS names for some other purposes than NAIs, though.

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