Re: [idn] Why follow IDNA with UTF-8?

["Eric A. Hall" <ehall@ehsco.com>]

> >  Wouldn't
> >it make sense to use UTF8 for the IDNs in the router maps, given its
> >usability with multiple languages?
> 
> Not necessarily. The format of the router maps could be plain text
> with UTF-8, plain text with ACE, ASN.1, and so on. You are mixing up
> document formats with DNS protocol.

Yes I am, because in this case, the document will be edited and its
contents reused later in SMTP and DNS. If we are encouraged to use UTF8
for the document contents by various OS and protocol issues, then we
should also be using UTF8 for the DNS parts.

> >  Furthermore, wouldn't it be beneficial
> >if the data and the IDN protocol both used the same encodings?
> 
> Probably, and that would be ACE.

Once a UTF8 format exists, why not leverage it? It would not be unheard of
for a new protocol to make such a demand. HTML 4.0 has different technical
demands than HTML 3.2, for example.

> >Clearly there are natural benefits to using UTF8 everywhere.
> 
> Sure, if you ignore most existing protocols and the severe problems
> during the wholesale upgrade of DNS servers.

What severe problems?

Is the need to upgrade ACE clients (and servers, unless you consider
manually editing ACE gobbledygook in zone files to be a wonderful feature)
also a severe problem?

> Have you now shifted
> from "ACE then UTF-8" to "never ACE"?

For new applications, there is absolutely the possibility that they will
be able to only specify the use of UTF8. This is a good thing, as new
applications can be written for international markets from the beginning,
and UTF8 is becoming very common. UTF8-in-DNS is an enabler. Furthermore I
would argue that it is absolutely critical to the next twenty years of
protocol work.

-- 
Eric A. Hall                                        http://www.ehsco.com/
Internet Core Protocols          http://www.oreilly.com/catalog/coreprot/