Re: [idn] I-D ACTION:draft-ietf-idn-idna-08.txt

[Dan Oscarsson <Dan.Oscarsson@trab.se>]

Adam M. Costello wrote:

>> IDNA must NOT restrict current usage and DNS standards making it
>> impossible to update the DNS standard later with a suitable defined
>> handling of non-ASCII octet values!
>
>The door is left open for updates to DNS:
>
>    If a signaling system which makes negotiation possible between old
>    and new DNS clients and servers is standardized in the future, the
>    encoding of the query in the DNS protocol itself can be changed from
>    ACE to something else, such as UTF-8.
>
>What we don't want to allow is untagged non-ASCII text in DNS messages,
>because there is no standard for what it means or how it should be
>compared.

It is simple to standardise it. We just publish a short RFC
defining how octet values with the 8th bit should be handled.

There are already DNS servers supporting names in UTF-8 and other
encodings. Why not standardise what encoding should be used?


>
>> IDNA is not an update of the DNS standard.
>
>IDNA is mainly orthogonal to the DNS standard, but it could be
>considered an update in one small respect.  RFCs 1034 and 1035 say:
>
>    domain name comparisons for all present domain functions are done in
>    a case-insensitive manner, assuming an ASCII character set, and a
>    high order zero bit.
>
>    Name servers and resolvers must compare labels in a case-insensitive
>    manner (i.e., A=a), assuming ASCII with zero parity.

Yes ASCII characters must have zero parity! This is because DNS uses 8
bit
octets, not 7bit ASCII.

>
>It seems pretty clear that the 8th bit is reserved for future use.
>As far as I know, no use for the 8th bit has ever been standardized.

Then it is high time it was standardised. Let's standardise it to
be UTF-8 as that is highly compatible with current usage.

>IDNA effectively says that the 8th bit is not to be used for
>internationalization, at least not for the time being.  It's still
>available for other purposes (like non-textual domain names).

That is bad, the 8th bit is already used for internationalisation!

   Dan