Re: [idn] Correction to draft-ietf-idn-idne-00

[James Seng <jseng@pobox.org.sg>]

Finally have the time to finish reading the I-D. Before anything else,
*excellent* work :-) The kind where we use UTF-8 without disrupting the
existing system.

However, this include changes in the DNS packet itself, I suggest that
to forward this to namedropper for comments.

-James "bored in DNSO" Seng

Paul Hoffman / IMC wrote:
> 
> Greetings again. Marc and I made a pretty bad mistake in the example
> in draft-ietf-idn-idne-00 that was caught by François Yergeau. We
> have turned in the -01 draft (with a few other minor changes), but
> wanted to get the corrected example to the list in case anyone was
> wondering what the heck it was that we were thinking.
> 
> 3.1.1 Basic example
> 
> The following example shows the label me.com where the "e" in "me" is
> replaced by a <LATIN CAPITAL LETTER E WITH ACUTE>, which is U+00C9. The
> decomposition and downcasing specified in [NAMEPREP] changes the second
> character to <LATIN SMALL LETTER E WITH ACUTE>, U+00E9. This string is
> then transformed using UTF-8 [RFC2279] to 0x6DC3A9.
> 
> Ignoring the other fields of the message, the domain name portion of the
> datagram could look like:
> 
>          +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
>       20 | 0  1  0  0  0  0  1  0| 0  0  0  0  0  0  1  1|
>          +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
>       22 |         0x6D (m)      |       0xC3 (e'(1))    |
>          +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
>       24 |         0xA9 (e'(2))  |       3               |
>          +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
>       26 |         0x63 (c)      |       0x6F (o)        |
>          +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
>       28 |         0x6D (m)      |       0x00            |
>          +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
> 
> Octet 20 means EDNS extended label type (0b01) using the IDN label
>        type (0b000010)
> Octet 21 means size of label is 3 octets following
> Octet 22-24 are the "m*" label encoded in UTF-8
> Octet 25-28 are "com" encoded as a STD13 label
> Octet 29 is the root domain
> 
> --Paul Hoffman, Director
> --Internet Mail Consortium