Re: [idn] Comparisons of the proposals

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

I guess many is in Adelaide, but here are some comments anyway.

>
> So,to be fair, I would say that zone file editing is much more easier in 
> utf-8 proposals than others: you edit what you want to see, tools are 
> available and work fine.

But it would be nice for me not to need a special editor when editing
zone files. That is why I in my DNS internationalisation draft
recommend DNS servers to handle loading of zone files from the
local character set and convert it into the standard used internally.

Some have said that you do not want to have zone files encoded in
ASCII compatibility encodings (ACE) like CIDNUC. In my draft, the zone
files will not be in an ACE format, instead the DNS server will,
if queried from non internatialisation aware DNS software, repond with
domain names encoded using ACE. And it is the DNS server that does
the encoding into ACE.

An unless the entire DNS is changed to use the ACE format (if you do,
you will have to have a separate DNS tree for that), you need to
have some way to know if a name is ACE encoded or in native DNS format.
As you have read in Paul's comparison, we have a prefix in cidnuc and
a trailing hyphen in my draft. A third alternative is to have a
prefix/suffix that is a checksum of the rest of the characters.
This tag takes some space, so ACE formats will be a little longer
because of that.

For those of you who want to study different possibilities of an ACE,
I have one more for you. In my draft I have a very simple ACE that
takes a lot of space so that long ACE names cannot be sent over
the wire through DNS. CIDNUC can be very compact but is difficult
to encode/decode. As my draft uses UTF-8 as the DNS standard format,
I want an ACE that is easy to encode/decode into UTF-8. I have
tried several, attached is a perl script implementing
encoding/decoding of my current idea: SACE (Simple ASCII Compatibility
Encoding). It is simple to encode/decode and will probably for many
names only be slightly longer than UTF-8. Within the 63 bytes
allowed by current DNS protocol a worst case for BMP will be 15
charcters. It is based on ideas from CIDNUC and UTF-5.
It is only intended to encode BMP. Leaving BMP you
must go international and use UTF-8.

   Dan

SACE.pm