Requirements for IDN and its Implementations from Japan Yoshiro YONEYA <yone@nic.ad.jp> JPNIC IDN-TF / NTT Software Co. 27 Mar 2000 IETF IDN-WG

Contents Scope Requirements for IDN Requirements for IDN Implementations Two experimental implementations of JPNIC Reference 27 Mar 2000 IETF IDN-WG

Scope Clarify our Requirements for IDN Discuss about Implementations of IDN Requirements (Core) Protocol Domain Name (Structure, etc.) Implementations 27 Mar 2000 IETF IDN-WG

Requirements for IDN IDN should be naturally readable and/or writable in its language context IDN should not require users to specify ZLD Current ASCII-only Domain Name should be usable in any language context But, IDN should not depend on natural language structure Word order, word separator, writing direction, etc. 27 Mar 2000 IETF IDN-WG

Requirements for IDN (Cont.) IDN should be a common framework to make localization easy Distinguish or unify of differences between characters should be a local (language depend) issue Examples in Japanese: ｱ (U+FF71)ア (U+30A2) (half-width vs. full-width) A (U+0041)Ａ (U+FF21) (half-width vs. full-width) ア (U+30A2)あ (U+3042) (katakana vs. hiragana) Guidelines for each language to deal with such issues should be documented in an RFC Set of characters usable as IDN label, canonicalization/normalization rule, etc. 27 Mar 2000 IETF IDN-WG

Requirements for IDN (Cont.) IDN should have enough length to store long labels JPNIC in Japanese is 社団法人日本ネットワークインフォメーションセンター Each IDN should have a corresponding ASCII-only domain name CNAME / DNAME like aliasing should be used to define IDN Reverse mapping should produce 1 or more ASCII-only name IDN character encoding should be stateless UTF-8 is desirable 27 Mar 2000 IETF IDN-WG

Requirements for Implementations Internationalization rules should be solved in DNS servers, localization rules should be solved in clients (resolvers) IDN capable DNS servers should not have regional dependence Maintenance supporting tools for IDN capable DNS servers may have regional dependence Conversion of charset and canonicalization and/or normalization should be done on the client side before query Proxy servers near clients may do them 27 Mar 2000 IETF IDN-WG

Requirements for Implementations (Cont.) IDN capable DNS servers should be fully upper compatible with current DNS Difference should be whether it can hold IDN New RRs such as to hold language selector should be examined Protocol extensions may be needed to distinguish languages strictly 27 Mar 2000 IETF IDN-WG

Requirements for Implementations (Cont.) Applications and resolvers should be 8bit through DNS protocol [RFC1035] is already 8bit through Prepare for migration/transition tools and/or proxy servers to prevent initial confusion URL character code converter, DNS proxy, etc. We should discuss about migration/transition strategy like IPv6 27 Mar 2000 IETF IDN-WG

Two experimental implementations of JPNIC IDNX/idnx-jp Proxy DNS server Accepts Japanese local charsets and converts them into UTF-5 Uses ZLD Worked well near clients side GDNS 8bit through based on BIND Uses CNAME for multilingual labels Not uses ZLD Worked well even in reverse mapping 27 Mar 2000 IETF IDN-WG

Reference JPNIC IDN-TF WebPage http://www.nic.ad.jp/en/research/idn/index.html 27 Mar 2000 IETF IDN-WG

Questions? 27 Mar 2000 IETF IDN-WG