[idn] Summary of TS-SC discussion

[Paul Hoffman / IMC <phoffman@imc.org>]

We have now rehashed every part of the question many times; maybe it 
is a good time to summarize.

1) Doing traditional-to-simplifed conversion must be done from a 
table; it cannot be done by algorithm.

2) No widely-accepted official standard table yet exists. Multiple 
different tables exist.

3) The same code points that would be converted in some domain name 
parts would not be converted in other domain name parts because the 
conversion is only appropriate for Chinese, not Korean or Japanese, 
which use the same code points. Thus, the language (not the script) 
must be known in order to do the conversion correctly.

4) There is no way to flag the language in name parts in a consistent 
way that end users would understand. Heuristics such as the TLD could 
be used, but doing so would cause some names to not be converted when 
they should be (such as a Chinese name part under .com) and would 
cause other names to be converted when they should not be (such as a 
Korean name part under a Chinese SLD). Hueristics such as language 
tagging would require that the end user tag each Chinese name part, 
and would not work at all with names that were cut and paste.

5) The problem can be definitively solved in zone files with multiple 
records. Some claim that this takes 2^length records, while others 
claim this takes 2 records.

6) Until the system is deployed, we cannot tell how well the users 
will adapt. We (the "experts" on domain names) can make predictions 
about what typical users will and won't be able to do, but we simply 
don't know, and our past track record at predictions is not all that 
good.

My conclusion from this is that we cannot standardize on 
traditional-to-simplified at this time with the protocols that are 
under discussion in the WG. We might be able to add this later after 
both a widely-accepted official standard table exists and a language 
tagging mechanism that makes sense to users is implemented.

Neither IDNA nor nameprep preclude this potential future change, so 
we can move forward with them now, and leave the door open to this 
change, and other similar changes, in the future.

--Paul Hoffman, Director
--Internet Mail Consortium