Internet Architecture Board


Internationalization Program

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Internationalization and Localization are two common aspects of user-facing systems which span locales.  Efforts in these two areas typically handle how to appropriately represent data in a specific context and how to carry it between contexts. This program currently focuses on a special case of this problem:  the set of systems which have no locale and how they interact with systems which rely on that context.  Work in this area involves complex tradeoffs along multiple dimensions, and there is rarely a single right answer.  Rather than attempting to force such an answer to emerge, the IAB will describe the problem, common patterns to analyse the trade-offs, and provide advice for managing specific instances of this issue.

This program will also maintain the IAB’s long term effort to maintain liaisons with relevant groups in this topic area. Among these are the Unicode Consortium, ICANN, and ISO/IEC JTC1 SC2.

Current work

A number of Internet protocols and systems rely on matching a known item for operation; when these lack access to locale or the facilities to process locale, they may fail or produce surprising results in the presence of multiple character composition methods. User names, passwords, and domain labels can each present this problem.  One of the most pressing issues for the general problem space noted above is resolving how internationalized names stored in the domain name system can be understood without a locale or similar context.

Internationalized names are currently stored in an ASCII-compatible encoding derived from the Unicode Standard.  That standard, however, includes certain characters which are visually identical but may be composed in multiple ways, the choice of which is locale-specific.  This creates an uncertainty in how a specific DNS label might be understood by other systems which rely on the DNS.  This issue is not limited to the DNS, but also occurs in other systems where a known-item match is expected; username and password matching are examples.  As originally described in the related IAB statement, this topic is currently blocking specific updates and is the program’s current priority.


IAB Members:

  • Ted Hardie (Program Lead)
  • Joe Hildebrand
  • Andrew Sullivan
  • Dave Thaler

Non-IAB Members:

  • Marc Blanchet
  • Francis Bond
  • Stuart Cheshire
  • Patrik Fältström
  • Heather Flanagan
  • Sarmad Hussain
  • John Klensin
  • Olaf Kolkman
  • Barry Leiba
  • Xing Li
  • Pete Resnick
  • Peter Saint-Andre
  • Yoshiro Yoneya

Mailing list:

Public discussion:

Past IAB Actions on I18N

  • Weider, C., Preston, C., Simonsen, K., Alvestrand, H., Atkinson, R., Crispin, M., and P. Svanberg, “The Report of the IAB Character Set Workshop held 29 February – 1 March, 1996″, RFC 2130, April 1997.
  • IAB and L. Daigle, Ed., “A Tangled Web: Issues of I18N, Domain Names, and the Other Internet protocols”, RFC 2825, May 2000.
  • IAB Response to Verisign GRS IDN Announcement, January 2003.
  • IAB to ICANN – IAB comments on ICANN IDN Guidelines, 14 October 2005.
  • IAB response to the Unicode Technical Consortium re:”Procedural Issues with the Liaison on Nextsteps”, 16 June 2006.
  • Klensin, J., Faltstrom, P., Karp, C., and IAB, “Review and Recommendations for Internationalized Domain Names (IDNs)”, RFC 4690, September 2006.
  • IAB liaison statement to ITU-T SG17 on the Review and Recommendations for Internationalized Domain Names, 2 October 2006.
  • IAB Technical Plenary on Internationalization at IETF 68 (minutes), 22 March 2007.
  • IAB Technical Plenary on Internationalization at IETF 76 (minutes), 12 November 2009.
  • Techchat on IDNA2008, Unicode, and UTR 46 (minutes), 7 April 2010.
  • IAB response to the IDNA appeal from JFC Morfin, 20 August 2010.
  • Thaler, D., Klensin, J., and S. Cheshire, “IAB Thoughts on Encodings for Internationalized Domain Names”, RFC 6055, February 2011.
  • IAB Statement on “The interpretation of rules in the ICANN gTLD Applicant Guidebook,” 8 February 2012.
  • Sullivan, A., Thaler, D., Klensin, J., and O. Kolkman, “Principles for Unicode Code Point Inclusion in Labels in the DNS”, RFC 6912, April 2013.
  • IAB Statement on Identifiers and Unicode 7.0.0, 11 February 2015