RFC 4343, "Domain Name System (DNS) Case Insensitivity Clarification", January 2006

Note: This RFC has been updated by RFC 5890

Errata ID: 6361
Status: Held for Document Update
Type: Technical
Publication Format(s) : TEXT
Reported By: Kaspar Etter
Date Reported: 2020-12-22
Held for Document Update by: Eric Vyncke
Date Held: 2021-01-04

Section 4.1 says:

No "case conversion" or "case folding" is done during such output operations, thus "preserving" case.

It should say:

?

Notes:

Whose case is preserved? The case of the label in the DNS query or the case of the label in the DNS database? In other words, if there is a DNS record for ietf.org and I query IETF.org, should the DNS response say ietf.org or IETF.org? I would expect it's the former so that the DNS administrator can inform the DNS requester about the preferred capitalization but I can't figure this out on the basis of the RFC. Does output case preservation refer to something else? All I observe is that tools like dig return the latter when I run 'dig IETF.org'. Maybe an errata is not the right place to ask for clarification but given the name of the RFC, I would expect to find a clear answer to this question in the RFC.

-- verifier note --
After discussion with the RFC author and the errata author, the conclusion is that the RFC isn't wrong but is arguably unclear for some readers.

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