Re: IESG Statement on IDN
"Randy Presuhn" <[email protected]> Tue, 11 Feb 2003 18:41:40 -0800
| Newsgroups | gmane.ietf.snmpv3 |
|---|---|
| Message-ID | <007d01c2d240$458550e0$7f1afea9@oemcomputer> |
Hi - Consequently, the value of sysName for such a system would be the ascii-encoded form of the IDNA name, right? Randy > From: "The IESG" <[email protected]> > To: <IETF-Announce:> > Sent: Tuesday, February 11, 2003 6:04 PM > Subject: IESG Statement on IDN > > > IESG Statement on IDN: > > IDNA [IDNA] specifies an encoding of characters in the Unicode > character repertoire [UNICODE] which is backwards-compatible with the > current definition of hostnames. This implies that domain names > encoded according to IDNA will be able to be transported between > peers using any existing protocol, including DNS. > > IDNA, through its requirement of Nameprep [NAMEPREP], uses equivalence > tables that are based only on the characters themselves; no attention > is paid to the intended language (if any) for the domain name. However, > for many domain names, the intended language of one or more parts of > the domain name actually does matter to the users. > > Similarly, many names cannot be presented and used without ambiguity > unless the scripts to which their characters belong are known. In both > cases, this additional information should be of concern to the registry. > > If there are no constraints on registration in a zone, people can > register combinations of characters in a manner that increases the > risk of misunderstandings, cybersquatting, and other forms of > confusion. A somewhat similar situation existed before the introduction > of IDNA exemplified by domain names such as example.com and examp1e.com > (note that the latter domain has the digit "1" instead of the letter > "L"). > > For some human languages, there are strings of characters that have > equivalent or near-equivalent meanings. When someone registers a name > containing such a string, the registry might want to automatically > generate a list of semantically or visually equivalent strings and > suggest that they also be registered. Further, some registries might > want to prevent particular characters for language-based reasons. > > Some registries, in particular the gTLD ones, are not naturally part > of any specific language group. In these cases, extra care must be > taken not to create unacceptable problems for any of the languages that > might be used. > > It is suggested that a registry act conservatively when starting to > accept IDNA-based domain names. Equivalences are very hard (if not > impossible) to define after registration has started. Assume that the > labels "x" and "y" at first are different, but later the tables for the > registry are changed so that "x" and "y" are then treated as being the > same. If x.example.com and y.example.com both were already registered > to different registrants, it is unclear which of them has to withdraw > the registration, how that selection process done, and so on. Thus, > having complete, publicly-stated policies before accepting > registration will lead to a much more stable registration process. > > There are also other problems that we know to be difficult when > dealing with IDNA-based domain names, for instance when to convert them > between their display format and their wire format, how to deal with > display formats on systems that do not support all of Unicode 3.2, and > how to deal with the problem of domain names in one format showing up > where names in the other format was expected by protocols or by people. > These problems are largely outside the scope of the IDNA standards > themselves, but they are of concern to anyone attempting to implement > the IDNA standard in products. See the IDNA specification for more > examples. > > The use of display-format IDNA-based domain names in other protocols > is not yet part of any standard; implementors are admonished to use > the wire format, i.e. ASCII-encoded, of the name until protocol > updates allowing the use of display format, e.g. Unicode-based > international character/glyph, are standardized. > > [IDNA] "Internationalizing Domain Names in Applications (IDNA)", > draft-ietf-idn-idna. > > [NAMEPREP] "Nameprep: A Stringprep Profile for Internationalized Domain > Names", draft-ietf-idn-nameprep. > > [UNICODE] The Unicode Consortium. The Unicode Standard, Version 3.2.0 > is defined by The Unicode Standard, Version 3.0 (Reading, MA, > Addison-Wesley, 2000. ISBN 0-201-61633-5), as amended by the Unicode > Standard Annex #27: Unicode 3.1 (http://www.unicode.org/reports/tr27/) > and by the Unicode Standard Annex #28: Unicode 3.2 > (http://www.unicode.org/reports/tr28/). >