referencing IDNA2008 (and IDNA2003?)

Andrew Sullivan ajs at
Thu Oct 21 21:58:26 CEST 2010

On Thu, Oct 21, 2010 at 10:12:16AM -0700, =JeffH wrote:
> 5.1.2.  Canonicalized host names
>    A canonicalized host name is the string generated by the following
>    algorithm:
>    1.  Convert the host name to a sequence of NR-LDH labels (see Section
> of [RFC5890]) and/or A-labels according to the
>        appropriate IDNA specification [RFC5891] or [RFC3490] (see
>        Section 6.3 of this specification)
>    2.  Convert the labels to lower case.
>    3.  Concatenate the labels, separating each label from the next with
>        a %x2E (".") character.

John had a remark about what "host name" means.  I just had a very
cursory look, but I don't see a definition of host name or a reference
to the relevant RFCs.  There's nothing in the above that decides
whether a given string is in fact a host name, as far as I can tell.
That might be ok; I don't know.

So what _is_ "host name" supposed to mean in the above?  Is this the
same as host name in RFC 952 as modified by RFC 1123?

I'd also suggest that you make a request to the DNS Directorate for a
review (you're likely to get one anyway, but this way you get in the
queue early).


Andrew Sullivan
ajs at
Shinkuro, Inc.

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