1. Requirements for IDN and its Implementations from Japan
Yoshiro YONEYA
JPNIC IDN-TF / NTT Software Co.
27 Mar 2000
IETF IDN-WG

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

3. 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

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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

11. Reference JPNIC IDN-TF WebPage
27 Mar 2000
IETF IDN-WG

12. Questions?
27 Mar 2000
IETF IDN-WG